The probability that a wedding costs less than $20,000 is approximately 0.3745.
The probability that a wedding costs between $20,000 and $31,000 is approximately 0.6188.
The minimum cost for a wedding to be included among the most expensive 5% of weddings is approximately $31,229.
(a) To find the probability that a wedding costs less than $20,000, we need to standardize the value of $20,000 by subtracting the mean and dividing by the standard deviation:
z = (20000 - 21858) / 5800 = -0.32
We can then use a standard normal distribution table or technology to find the corresponding probability:
P(z < -0.32) ≈ 0.3745
Therefore, the probability that a wedding costs less than $20,000 is approximately 0.3745.
(b) To find the probability that a wedding costs between $20,000 and $31,000, we need to standardize both values and find the area between the corresponding z-scores:
z1 = (20000 - 21858) / 5800 = -0.32
z2 = (31000 - 21858) / 5800 = 1.58
Using a standard normal distribution table or technology, we can find the probabilities:
P(-0.32 < z < 1.58) ≈ 0.6188
Therefore, the probability that a wedding costs between $20,000 and $31,000 is approximately 0.6188.
(c) To find the minimum cost for a wedding to be included among the most expensive 5% of weddings, we need to find the z-score that corresponds to the 95th percentile of the standard normal distribution. We can use a standard normal distribution table or technology to find this value:
z = invNorm(0.95) ≈ 1.645
We can then use the formula for standardizing a value to find the minimum cost:
z = (x - 21858) / 5800
Solving for x, we get:
x = z(5800) + 21858
x = 1.645(5800) + 21858
x ≈ 31229
Therefore, the minimum cost for a wedding to be included among the most expensive 5% of weddings is approximately $31,229.
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Which one of the following is true regarding the use of the mode, mean, and median for different levels of measurement?
The mode, mean, and median are all valid measures of central tendency for interval and ratio level data. For nominal level data, only the mode is appropriate, while for ordinal level data, both the mode and median can be used, but the mean is not recommended as it assumes equal intervals between categories.
The correct statement regarding the use of the mode, mean, and median for different levels of measurement is:
The mode can be used for nominal and ordinal levels of measurement, the median is used for ordinal, interval, and ratio levels, while the mean is used for interval and ratio levels of measurement.
Let's break it down:
1. Mode: applicable to nominal and ordinal levels as it represents the most frequently occurring value in the data.
2. Median: applicable to ordinal, interval, and ratio levels as it represents the middle value when data is arranged in order.
3. Mean: applicable to interval and ratio levels as it represents the average value by summing all data points and dividing by the number of data points.
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3(n + 5) is equivalent to (n + p)3.
Answer:
[tex]3(n + 5) = (n + 5)3[/tex]
So p = 5.
what is the value of the expression
2/-3 x -1/5
The point A is shown below.
Reflect A across the x-axis.
Then reflect the result across the y-axis.
Plot the final point.
Important: Only plot the final point in your answer.
8-1
X
5
The coordinate of final point of A after transformation is,
A'' = (0, - 7)
We have to given that;
Coordinate of A = (0, 7)
We know that;
Rule for the across the x - axis is,
(x, y) = (x , - y)
Hence, We get;
Point after transformation is,
A' = (0, - 7)
And, Rule for the across the y - axis is,
(x, y) = (-x , y)
Hence, Point after transformation is,
A'' = (0, - 7)
Thus, The coordinate of final point of A after transformation is,
A'' = (0, - 7)
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Sophia, Malcolm, and Oren are playing a money game. Their bank
balances are shown in the table. Complete the table by writing the
absolute value of each bank balance to show how much each
player owes. Who owes the greatest amount?
Bank Balance Amount Owed
-$150
- $325
- $275
Answer:
Please mark me the brainliest
Bank Balance | Amount Owed
---------------------|-------------
-$150 | $150
-$325 | $325
-$275 | $275
To find the amount owed, we simply take the absolute value of each bank balance. The player who owes the greatest amount is the one with the largest absolute value bank balance. In this case, that would be Malcolm, who owes $325.
Step-by-step explanation:
Both of these groups started with 22, 6-sided dice and followed the same procedure for removing dice until they had no dice left. How could they end up with such different scatterplots? Does it make sense that one set of data could look so possibly linear while the other does not?
It is possible for one set of data to have a scatterplot that appears linear while the other does not, even if both groups started with the same number of dice and followed the same removal procedure.
This is because the way the dice were removed could have been different between the two groups, leading to different patterns of results. Additionally, other factors such as the order in which the dice were removed or the number of trials conducted could also affect the resulting scatterplot.
Ultimately, the scatterplot is a visual representation of the relationship between the variables being measured, and it can take on many different forms depending on the specific data and conditions being analyzed.
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If the slope of a line is 5/8 and the run of a triangle connecting two points on the line is 16, what is the rise?
The rise of the line that has a slope of 5/8 and a run of 16 is calculated as: 10.
What is the Slope of a Line?The slope of a line is defined as the ratio of the rise of the line to the run of the line. This can also be defined as change in y over the change in x of a line.
Given the following:
Slope of a line (m) = 5/8
Run of the triangle = 16
Rise = x
Using the slope formula, we have:
Slope of a line (m) = rise/run
5/8 = x/16
Solve for x:
x = (5 * 16) / 8
x = 80/8
x = 10
Therefore, we can conclude that the rise is 10.
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Key Question #20 1. For f(x)= x, determine the average rate of change of f(x) with respect to x over each interval. a. 1
The average rate of change of f(x) = x with respect to x over the interval a = 1 is 1.
To determine the average rate of change of f(x) = x with respect to x over the interval a, we'll use the formula:
Average Rate of Change = (f(b) - f(a)) / (b - a)
In this case, the interval a is 1, so let's choose an interval b. We can use any value for b, but let's choose b = 2 for simplicity.
Step 1: Find f(a) and f(b)
f(x) = x, so:
f(1) = 1
f(2) = 2
Step 2: Plug the values into the formula
Average Rate of Change = (f(2) - f(1)) / (2 - 1)
Average Rate of Change = (2 - 1) / (2 - 1)
Step 3: Calculate the result
Average Rate of Change = (1) / (1)
The average rate of change of f(x) = x with respect to x over the interval a = 1 is 1.
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x-3y= -9 slope intercept form
Answer:
[tex]\textsf{y=\frac{1}{3}x+3}[/tex][tex]y = \frac{1}{3} x+3[/tex]
Step-by-step explanation
[tex]\textsf{*slope intercept form: y = mx +b}[/tex]
---------------------------------------------
[tex]\textsf{x - 3y = -9}[/tex]
Subtract x from both sides:
[tex]\textsf{-3y = -x - 9}[/tex]
Divide both sides by -3:
-3y/-3 = -x/-3 - 9/-3
[tex]\textsf{y = 1/3x +3}[/tex]
[tex]-jurii[/tex]
An amount is increased by 20% 40% of the new amount is 288 Work out the original amount.
Researchers studying osteoporosis (bone loss) suspected that women over the age of 50 in the United
States are diagnosed with the disease more often than women over 50 in Mexico. They took a random
sample of 200 women over the age of 50 from each country. Here are the results:
Diagnosed with osteoporosis? US. Mexico
Yes. 40. 20
No 160 180
Total 200. 200
The researchers want to use these results to test He: pus - PM = 0 versus H₂: Pus-PM > 0.
Assume that all conditions have been met.
What is the P-value associated with these sample results?
a. P-value is greater than or equal to
0.20
b. 0.05 is less than or equal to the P-
value < 0.10
c. 0.10 is less than or equal to the P-
value < 0.20
d. P-value < 0.01
e. 0.01 is less than or equal to the P-
value < 0.05
Answer:
A P-value < 0.01
Step-by-step explanation:
suppose you are interested in using regression analysis to estimate an nba player's salary using the following independent variables: the player was traded in the last 5 years, player's age, player's height, career free throw percentage, average points per game, and the team had greater than 45 wins in the previous season. which of the following independent variables are indicator (dummy) variables? select all that apply.
Based on the information provided, only one of the independent variables can be an indicator (dummy) variable, which is:
- The player was traded in the last 5 years
Based on the information provided, only one of the independent variables can be an indicator (dummy) variable, which is:
- The player was traded in the last 5 years
This variable can take on a value of 0 or 1, where 0 represents that the player was not traded in the last 5 years, and 1 represents that the player was traded in the last 5 years. The other independent variables are continuous variables (e.g., player's age, player's height, career free throw percentage, average points per game) or categorical variables that do not need to be represented as dummy variables (e.g., the team had greater than 45 wins in the previous season).
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A circular region has a population of about 175,000 people and a population density of about 1318 people per square mile. Find the radius of the region. Round your answer to the nearest tenth.
The radius of the region is 11.55 mile.
We have,
Population = 175,000
So, population density
= 175,000 / 1318
= 132.77
and, the radius using from the population density
Radius = √area / (22/7)
= √1318 x 7/22
= 11.55 mile
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Express in the form of a rational number: 0.1212….
Answer:
[tex]0.1212...=\dfrac{4}{33}[/tex]
Step-by-step explanation:
A repeating decimal is a decimal number with a digit (or group of digits) that repeats forever.
There are three ways to show a repeating decimal:
Several duplicates of the repeating digit or block of digits, followed by an ellipsis, e.g. 0.3333... or 0.123123...A dot or a line above a repeated digit, e.g. [tex]\sf 0.\.{3}[/tex] or [tex]\sf 0.\overline{3}[/tex]A line above a repeating block of multiple digits, e.g. [tex]\sf 0.\overline{123}[/tex]0.1212... is a repeating decimal as there are two duplicates of the repeating block of digits "12" followed by an ellipsis.
To express a repeating decimal as a rational number, begin by assigning the decimal to a variable:
[tex]x=0.1212...=0.\overline{12}[/tex]
Multiply both sides by 100:
[tex]\implies x \cdot 100=0.\overline{12}\cdot 100[/tex]
[tex]\implies 100x=12.\overline{12}[/tex]
Subtract the first equation from the second to eliminate the part after the decimal:
[tex]\begin{array}{crcr}& 100x & = & 12.\overline{12}\\- & x & = & 0.\overline{12}\\\cline{2-4} & 99x & = & 12\phantom{.12}\\\end{array}[/tex]
Divide both sides of the equation by 99:
[tex]\implies \dfrac{99x}{99}=\dfrac{12}{99}[/tex]
[tex]\implies x=\dfrac{12}{99}[/tex]
Reduce the fraction to is simplest form by dividing the numerator and denominator by 3:
[tex]\implies x=\dfrac{12 \div 3}{99 \div 3}=\dfrac{4}{33}[/tex]
[tex]\textsf{Therefore, $0.1212...$ expressed in the form of a rational number is\;$\dfrac{4}{33}$}.[/tex]
What is the coefficient of x^3 term in the power series expansion (or Taylor's expansion) of f(x) = e^(x) sin(x)
The coefficient of x³ term in the power series expansion of f(x) = [tex]e^x[/tex] sin(x) is 1/15.
To find the coefficient of x³ term in the power series expansion of f(x) = [tex]e^x[/tex] sin(x), we need to write the Taylor series for [tex]e^x[/tex] and sin(x) and then multiply them to get the Taylor series for f(x). The Taylor series for e^x is:
[tex]e^x[/tex] = 1 + x + (x²/2!) + (x³/3!) + ...
The Taylor series for sin(x) is:
sin(x) = x - (x³/3!) + (x⁵/5!) - ...
Multiplying these two series, we get:
f(x) = [tex]e^x[/tex] sin(x) = (1 + x + (x²/2!) + (x³/3!) + ...) × (x - (x³/3!) + (x⁵/5!) - ...)
Expanding this out and collecting the terms with x³, we get:
f(x) = x - (x³/3!) + (7x³/5!) + ...
Therefore, the coefficient of x³ term in the power series expansion of f(x) = [tex]e^x[/tex] sin(x) is -1/6 + 7/120 = 1/15.
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Estimate the perimeter and the area of the shaded figure.
The perimeter and area of the given polygon are:
Perimeter = 22.325 units
Area = 25 square units
How to find the area and perimeter?Using Pythagoras theorem, we can find the length of the sides of the polygon as:
a = √(1² + 3²)
a = √10
b = √(3² + 3²)
b = 2√9
c = √(3² + 3²)
c = 2√9
d = √(1² + 3²)
d = √10
e = 4
Thus:
Perimeter = 2√10 + 4√9 + 4
Perimeter = 22.325 units
Area = 2(¹/₂ * 1 * 3) + 2(¹/₂ * 3 * 3) + (4 * 3)
= 25 square units
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Is the number of sit-ups Anna does proportional to the time she spends doing them?
No, the number of sit-ups Anna does, is not proportional to the time she spends doing them.
When Anna starts doing sit-ups for her first triathlon, she does a sit-up every 22 seconds. But we know that as she gets tired, each sit-up takes longer and longer to do. The situps may take 40 seconds or 75 seconds as she gets more tired.
As we can see that there is no constant rate at which she gets tired and take more seconds to do sit-ups. In order to be proportional, the increasing or decreasing rate should be constant. We can see that the time she spends doing them is not increasing or decreasing at a constant rate along with the number of sit-ups she is doing.
Therefore, the number of sit-ups Anna does is not proportional to the time she spends doing them.
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The complete question is "Anna does sit-ups to get ready for her first triathlon. When she starts, she does a sit-up every 22 seconds. But, as she gets tired, each sit-up takes longer and longer to do. Is the number of sit-ups Anna does proportional to the time she spends doing them? "
Suppose a bag contains 4 white chips and 6 black chips. What is the probability of randomly choosing a black chip, not replacing it, and then randomly choosing another black chip?
The probability of choosing a black chip and then another black chip is,
⇒ 1/3
Since, There are 4 + 6 = 10 chips in the bag.
And, 6 of them are black .
Hence, The probability that the first chip chosen will be black is,
⇒ 6/10
⇒ 3/5.
After that, there is one black chip less in the bag, so there are 9 chips in the bag, 5 of them are black.
Hence, The probability that the second chip chosen will be black is,
⇒ 5/9
Now, Multiply the probabilities to find the probability that the first chip will be black and the second chip will be black:
⇒ 3/5 × 5/9
⇒ 1/3
Thus, The probability of choosing a black chip and then another black chip is,
⇒ 1/3
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Annabel is comparing the distances that two electric cars can travelafter the battery is fully charged
After the battery is fully charged, Car B can go further than Car A. Car B, as compared to Car A, had lower variability measurements. After the battery is completely charged, Car B can go further than Car A since Car A has a lower mean and median. Option D is Correct.
The median splits the data in half. A lower median indicates that Car A has less mileage than Car B.
Two measurements exist.
The measure of centre reveals how closely or widely the data are dispersed around the centre.
The measurements of centre are mean, median, and mode.
Car A travelled less since it had a lower mean and median.
We can find out how data changes with a single value using the measure of variability. The data is denser at the mean when the MAD is less. The MAD in Car B is lower. Data that is closer to the centre of the data set has a smaller IQR.
IQR is lower in Car B.
Consequently, automobile B travelled steadily since its IQR and MAD were lower. Option D is Correct.
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Correct Question:
Annabel is comparing the distances that two electric cars can travel after the battery is fully charged. Car A (miles) Car B (miles) Mean 145 200 Median 142 196 IQR 8 4 MAD 6 2 Part A Use the measures of center to make an inference about the data. Use the drop-down menus to complete your answer. Car A can travel further than Car B after the battery is fully charged. Part B Based on the data, which car performs most consistently? Explain. A. Car A because the measures of center are smaller for Car A than for Car B. B. Car B because the measures of center are smaller for Car B than for Car A. C. Car A because the measures of variability are smaller for Car A than for Car B. D. Car B because the measures of variability are smaller for Car B than for Car A.
Classifiy the triangle by using its side lengths
Answer: Where is the triangle?
Step-by-step explanation: Brainliest pls:)
Algibra 1, unit 5! Help
Answer: -15
Step-by-step explanation:
x+y=10
y=-x+10
2x+3(-x+10)=45
2x-3x+30=45
-x=15
x=-15
Suppose that it is known that on any given day in the month ofmarch there is a 0.3 probability of rain. Find the standarddeviation of rainy days in March.
The standard deviation of rainy days in March is approximately 2.55 days.
To find the standard deviation of rainy days in March, we first need to determine the expected value or the mean number of rainy days in March.
The expected value of a binomial distribution can be found using the formula: E(X) = np, where X is the random variable representing the number of rainy days in March, n is the number of trials (days in March), and p is the probability of success (rain) on a given day.
In this case, n = 31 (number of days in March) and p = 0.3 (probability of rain on any given day in March). Therefore, the expected value of rainy days in March is
E(X) = np = 31 × 0.3 = 9.3
Next, we need to find the variance of the binomial distribution, which is given by the formula: Var(X) = np(1 - p).
Var(X) = 31 × 0.3 × (1 - 0.3) = 6.51
Finally, the standard deviation of rainy days in March is the square root of the variance:
SD(X) = √Var(X) = √6.51 ≈ 2.55
Therefore, the standard deviation of rainy days in March is approximately 2.55 days.
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Show work and please explain how to solve it!
The density of the ball in the air is given as follows:
d = 4 x 10^5 ounces/ft³.
How to calculate the density?The density is calculated as the division of the mass by the volume of an object, as follows:
d = m/v.
The ball in this problem is spherical with a diameter of 0.05 feet = radius of 0.025 feet, hence the volume is given as follows:
V = 4 x 3.1416 x 0.025³/3
V = 6.545 x 10^-5 ft³.
The ball in the air is inflated, hence the mass is given as follows:
m = 22.93 ounces.
Thus the density of the ball is given as follows:
d = 22.93/(6.545 x 10^-5)
d = 4 x 10^5 ounces/ft³.
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Phil is a 21-year-old male. What is his life expectancy? Male Female Deaths Per 1,000 Life Expectancy (Years) Probabillity of Living to This Age Deaths Per 1,000 Life Expectancy (Years) Probabillity of Living to This Age Age 19 1.0 58.2 0.9907 0.5 62.2 0.9940 20 1.0 57.2 0.9897 0.5 61.3 0.9935 21 1.0 56.3 0.9888 0.5 60.3 0.9930 22 1.0 55.3 0.9878 0.5 59.3 0.9925A. 56.3 years B. 77.3 years C. 77.2 years D. 55.3 years
Phil's life expectancy is 56.3 years.
Based on the provided data, the life expectancy for Phil, a 21-year-old male, is 56.3 years. Therefore, the correct answer is 56.3 years.
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calculate the moment of inertia when an object's mass is 12 kg and the mass is distributed 4 meters from the axis of rotation.
To calculate the moment of inertia of an object, you need to know its mass and the distance it is from the axis of rotation. In this case, the object has a mass of 12 kg and is distributed 4 meters from the axis of rotation. The formula to calculate the moment of inertia is I = mr^2, where the moment of inertia, m is the mass, and r is the distance from the axis of rotation.
Using this formula, we can calculate the moment of inertia of the object:
I = 12 kg x (4 m)^2
I = 192 kgm^2
Therefore, the moment of inertia of the object is 192 kgm^2.
To calculate the moment of inertia for an object, you can use the following formula:
Moment of Inertia (I) = Mass (m) × Distance² (r²)
Given the object's mass is 12 kg and the mass is distributed 4 meters from the axis of rotation, we can plug these values into the formula:
I = 12 kg × (4 m)²
Now, we'll square the distance:
I = 12 kg × 16 m²
Finally, multiply the mass and the squared distance:
I = 192 kg·m²
So, the moment of inertia of the object is 192 kg·m².
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how can i prove 1/xy = 1/x * 1/y
To prove that 1/xy = 1/x * 1/y, we can start by multiplying both sides of the equation by xy.
Multiplying both sides of the equation by xy gives us:
1 = xy * 1/x * 1/y
Next, we can simplify the right-hand side by canceling out the x and y terms that appear in both the numerator and denominator:
1 = y/x + x/y
To further simplify this expression, we can multiply both sides by xy:
xy = y^2 + x^2
This equation can be rearranged to get:
x^2 + y^2 = xy
Finally, we can use the formula for the sum of squares:
x^2 + y^2 = (x+y)^2 - 2xy
Substituting this into the previous equation, we get:
(x+y)^2 - 2xy = xy
Simplifying, we get:
(x+y)^2 = 3xy
Taking the square root of both sides, we get:
x+y = sqrt(3xy)
Dividing both sides by xy, we get:
1/xy = 1/x * 1/y
Therefore, we have proven that 1/xy = 1/x * 1/y.
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Which data table indicates a positive linear association between the hours worked and the daily wages of waiters in a restaurant?
Answer:
Step-by-step explanation:
To determine if there is a positive linear association between the hours worked and the daily wages of waiters in a restaurant, you can create a scatter plot of the data and look for a pattern.
Once you have the data, you can use a statistical software or a spreadsheet program to create a scatter plot. You can then visually inspect the scatter plot to see if there is a clear pattern of a positive linear association between the two variables.
If there is a positive linear association, the data points on the scatter plot will form a roughly straight line that slopes upwards from left to right. The closer the data points are to the line, the stronger the association.
So, the data table that indicates a positive linear association between the hours worked and the daily wages of waiters in a restaurant is the one where the scatter plot shows a clear upward trend.
Calculate the surface area.
25 square inches
120 square inches
126 square inches
132 square inches
The surface area of the figure is 132 square units.
Option D is the correct answer.
We have,
The figure has two types of shapes.
- 3 rectangles
- 2 triangles
Now,
Area of the 3 rectangles.
= 5 x 10 + 4 x 10 + 3 x 10
= 50 + 40 + 30
= 120 square units
Area of 2 triangles.
= 1/2 x 4 x 3 + 1/2 x 4 x 3
= 1/2 x 12 + 1/2 x 12
= 6 + 6
= 12 square units
Now,
Total surface area.
= 120 + 12
= 132 square units.
Thus,
The surface area of the figure is 132 square units.
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frankie has a new cell phone plan. he will pay a one-time activation fee of 30$, and 45$ each month. which equation can be used to determine the total amount, t, Frankie will have spent after m months on his cell phone plan
The equation which can be used to determine the total amount, t, Frankie will have spent after m months on his cell phone plan is t = 30 + 45m.
Given that,
Frankie has a new cell phone plan.
He will pay a one-time activation fee of 30$, and 45$ each month.
One time activation fee = $30
Amount each month = $45
Amount for m months = 45m
Total amount for the plan = 30 + 45m
If t represents the total amount for the cell phone activation plan, the required equation can be written as,
t = 30 + 45m
Hence the required equation for the cell phone plan is t = 30 + 45m.
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You have a combination lock that has the numbers 1-40 on the dial. You
forgot the combination, but you remember that the combination is three
numbers, the last digit of all three numbers is 6, and none of the numbers
are between 1 and 10. You make a random guess with what you know.
What is the probability that you will get the combination?
Answer:
1/870 ≈ 0.0011494 or about 0.115% (rounded to 6 decimal places)
Step-by-step explanation:
The first digit can be any of the numbers between 10 and 40, except for those that end in 6 (since the last digit of all three numbers is 6). This leaves us with 30 numbers to choose from for the first digit. Similarly, the second digit can be any of the numbers between 10 and 40, except for those that end in 6 and the one chosen for the first digit. This leaves us with 29 numbers to choose from for the second digit.
For the third digit, we have only one option since we know it ends in 6.
So the total number of possible combinations is:
30 * 29 * 1 = 870
Out of these, only one combination is the correct one. Therefore, the probability of guessing the combination correctly on the first try is:
1/870 ≈ 0.0011494 or about 0.115% (rounded to 6 decimal places)