Question

if 25% of a certain number is 1600 what is 10% of that number

Answer 1

Let the number be x
according to the sum
25% of x = 1600
⇒25/100*x = 1600
therefore x = 6400
and then 10% of x = 10/100*6400 = 640

Answer 2

the answer is 640

hope it helps....