20.4 is what percent of 17 ,

Question

Also 20.57 is 42.5% of what # 

Answer 1

Hi Free,

 

    20.4 is what percent of 17.

 

             20.4  =   x

            -----       ---

              17        100

 

The equation is set up as part over whole = part over 100  (since it is percent).  To solve the equation cross multiply.

  

           20.4(100) = x

          -----------

               17

 

 

                 120=x    

Why is 120%?  

   It is 120% because 20.4 is greater than 17.

 

ANSWER:  120%

 

Now for your 2nd question.

Also 20.57 is 42.5% of what #

 

42.5% is .425 as a decimal:             .425x=20.57

Divide both sides by .425                      x=48.4

 

   ANSWER:  The number is 48.4

 

Hope this process helps you.

 

           

Answer 2

Hi Free,

 

The easiest way to solve these types of problems is to set up a proportion.

 

If you were asked, 5 is what percent of 10 (you know the answer is 1/2 or 50%), you would write 5/10 = X/100, cross multiply and get X = 50%.

 

Now you can try this with the first problem above.

 

For the second problem, this is the same as asking 5 is 50% of what number.  So you set up this proportion-->

 

5/X = 50/100, cross multiply and you get X = 10.

 

Now you can try this with the second problem.

 

Have fun.

 

Dan