Question

15 is what percent of 40?

Answer 1

To get the solution, we are looking for, we need to point out what we know. 

1. We assume, that the number 40 is 100% - because it's the output value of the task. 
2. We assume, that x is the value we are looking for. 
3. If 100% equals 40, so we can write it down as 100%=40. 
4. We know, that x% equals 15 of the output value, so we can write it down as x%=15. 
5. Now we have two simple equations:
1) 100%=40
2) x%=15
where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that:
100%/x%=40/15
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 15 is what percent of 40

100%/x%=40/15
(100/x)*x=(40/15)*x       - we multiply both sides of the equation by x
100=2.66666666667*x       - we divide both sides of the equation by (2.66666666667) to get x
100/2.66666666667=x 
37.5=x 
x=37.5

now we have: 
15 is 37.5% of 40

Answer 2

Answer:

We will get 15 is 37.5% of 40.

Step-by-step explanation:

        Given data:- 15 is x% of 40.

        To find:-Value of x%.

        Solution:-

• A percentage is a fraction of an amount expressed as a particular number of hundredths of that amount.

• It is denoted by %.

• We are using the unitary method to calculate the percentage of numbers.

• Fractions can be converted into percentages and vice-versa.

        Therefore,

         $15\ is \ x\%\ of\ 40\\=>\frac{x}{100} \times40=15\\=>\frac{40x}{100}=15\\=>40x=15\times100\\=>40x=1500\\=>x=\frac{1500}{40}\\=>x=\frac{75}{2} \\=>x=37.5\%$