0.85 is 25% of what sum?

Question

Step by step process 

Answer 1

 

Letting s be the sum:

 

   25% of s  is 0.25s   ("of" is a cue for multiplication)

   

[ Percentages are nothing more than fractions with 100 in the denominator,

     so 25% is  25/100 = 0.25 ]

 

The part "0.85 is"  implies  "0.85 ="     ("is" is a cue for an "=" sign)

 

So they are asking to find s for   0.85 = 0.25s

 

Divide both sides by 0.25:     0.85/0.25 = 0.25s/0.25  (we want exactly 1 "s")  

Carry out the division:          3.40 = 1s

 

That's it, the sum is 3.40

 

Check:  25% of 3.40 = (0.25)(3.40) = 0.85   (ok)