Here is a riddle:
I am thinking of two numbers that add up to 5.678.
The difference between them is 9.876.
What are the two numbers?

Answer:

The answer is c. 8x

Answer:

30

Step-by-step explanation:

2x+5x= 105

7x= 105

x= 105/7

x= 15

First part= 2x= 2(15)= 30

9514 1404 393

Answer:

Step-by-step explanation:

Let a, b, c represent the quantities of 20%, 35%, and 55% solutions, respectively. Then for the given mix, we have ...

  a + b + c = 108 . . . . . total number of liters

  .20a +.35b +.55c = 0.40·108 . . . . . liters of acid

  0a - 3b + c = 0 . . . . . 55% solution was 3 times 35% solution

__

Solving these three equations by your favorite method gives ...

  (a, b, c) = (36, 18, 54)

The chemist used 36 liters of 20%, 18 liters of 35%, and 54 liters of 55%.

_____

Comment on alternate approach

Since the ratio of 55% to 35% is 3 : 1, that mix will have an acid content of ...

  (3(.55) +1(.35))/4 = 0.50 = 50%

So, the final mix is equivalent to some quantity of 50% mix being added to some quantity of 20% mix. The fraction that is 50% mix* will be (40-20)/(50-20) = 2/3 of the total, or (2/3)(108 L) = 72 L.

Now we know that (1/3)(108 L) = 36 L of 20% solution is needed and (1/4)(72 L) = 18 L of 35% solution is needed. 3 times that is 54 L of 55% solution.

__

* After you work a few mixture problems, you can see the pattern. If we start with an equation for x = fraction of 50% to use with 20% to make 40%, we get ...

  x(50%) +(1 -x)(20%) = 40%

  x(50% -20%) = 40% -20% . . . . . subtract 1(20%) and factor out x

  x = (40% -20%)/(50% -20%)

The key here is to see where the numbers 20%, 40%, and 50% show up in the fraction.

Answer:

2 3

Step-by-step explanation:

Answer:

The old photo frame is still rectangular

Step-by-step explanation:

Rectangles

The rectangle shape can be identified because it has 4 internal angles of 90° each. The diagonal forms with two adjacent sides a right triangle where the Pythagora's Theorem must stand. Being a and b the length of the sides of the rectangle and d the diagonal, then:

[tex]d^2=a^2+b^2[/tex]

Vince's photo frame has dimensions of 8 inches and 6 inches, with a diagonal of 10 inches. If the above condition is met, then the frame is still rectangular.

Calculating:

[tex]10^2=6^2+8^2[/tex]

[tex]100=36+64[/tex]

[tex]100=100[/tex]

Since the condition is met, the old photo frame is still rectangular

Answer: we can’t see graphs but I can help you if you show me them

Step-by-step explanation:

Answer:

Step-by-step explanation:

3(x + 1) − (3x + 2)

we will expand the first bracket:

3x+3-3x-2

3x and -3x cancels

3-2=1

Answer:

1

Step-by-step explanation:

3x+3+−3x+−2

=(3x+−3x)+(3+−2)

=1

Step-by-step explanation:

The answer is the third option

Answer: A im positive its A

Step-by-step explanation: 3 times 2 equals 6 and add that to 3 times 4 which is 12 and you get 18

Answer:

The ratio 20:30 is not equivalent to 1:2.

Answer:

The third answer, y = 4x + 1

Step-by-step explanation:

Let's take the pair x = 2, and y = 9.

We know what x is, and what the result, y, is now.

Let's plug x into the third equation, y = 4x + 1

y = 4 * 2 + 1

y = 8 + 1

y = 9

We already know that y = 9, so this equation is correct.

Hope this helps!

(Let me know if you want to know why it's not any of the others.)

Answer:

13 weeks

Step-by-step explanation:

Let's say the number of weeks she will take is x. This would mean that 4.25 times the number of weeks(x) is equal to 55.25

Equation:

4.25x = 55.25

x=13

Answer

x^(2)    x to the second power

Step-by-step explanation:

To divide exponents (or powers) with the same base, subtract the exponents. Division is the opposite of multiplication, so it makes sense that because you add exponents when multiplying numbers with the same base, you subtract the exponents when dividing numbers with the same base.

Answer:

Option (4)

Step-by-step explanation:

STEP - 1

cos(x + y)

STEP - 2

[tex]\text{sin}[\frac{\pi}{2}-(x+y)][/tex]

STEP - 3

[tex]\text{sin}[(\frac{\pi}{2}-x)-y][/tex]

STEP - 4

[tex]\text{sin}(\frac{\pi}{2}-x)\text{cos}(-y)+\text{cos}(\frac{\pi}{2}-x)\text{sin}(-y)[/tex]

STEP - 5

cos(x)cos(y) - sin(x)sin(y)

[Since, [tex]\text{sin}(\frac{\pi}{2}-x)=cos(x)[/tex] and [tex]\text{cos}(\frac{\pi}{2}-x)=\text{sin}(x)[/tex]]

[Since, cos(-x) = cos(x) and sin(-x) = -sin(x)]

Therefore, Option (4) will be the correct option.

Answer:

D

Step-by-step explanation:

Top Answer was right, don't know why it was rated poorly

Answer:

4

Step-by-step explanation:

Answer:

Add three zeros to the end.

Step-by-step explanation:

When you add three zeros, the result is equivalent to when multiplying by 1000. For example, 20 times 1000 is 20,000.

Hi! I believe your answer is 3 zeros. For example, 7 × 1,000 = 7,000 (add 3 zeros). I hope this helps you! Good luck and have a great day/night. ❤️✨

Answer:

44%

Step-by-step explanation:

Answer:

Step-by-step explanation:

1. 9.6x10^4

2. 7.2x10^8

3. 1.19x10^-7

4. 9.48x10^-3

5. 2.04x10^8

Answer:

Tallahassee

Step-by-step explanation:

Answer:

$9

Step-by-step explanation:

divide 45 and 5, you get 9

Answer:

45.00$ divided by 5.00$ is 9.00$

i hoped this helped!

Step-by-step explanation:

Answer:

Add the information, and find the second number.

Step-by-step explanation:

"She throws them 8.49 m/s high"

8.49 + ? = ?

"Her friend catches them 2.89 m/s higher"

8.49 - 2.89 = 5.60

The reason why you must subtract is because it is asking how high it is in the air, going up and down.

8.49 + 5.60 = ?

8.49 + 5.60 = 14.09

Which means, it was in the air for 14.09 m/s.

Answer:

Step-by-step explanation:

6 miles

2 times 3 = 6

or

2 x 3/3 = 6

Answer:

B.

Step-by-step explanation:

3(4x-2)-30=-6(6-2x)-20

12x-6-30=-36+12x-20

12x-36=12x-56

Answer:

[tex]\frac{5}{9}[/tex]

Step-by-step explanation:

Given

[tex]\frac{45}{81}[/tex] ( divide numerator and denominator by HCF of 9 )

= [tex]\frac{5}{9}[/tex] ← in simplest form

Answer:

126.38

Step-by-step explanation:

$135.00-$8.62=$126.38