Question

13 percent of what is 78

Answer 1

I think the answer is 600

Answer 2

13% of what is 78

"what" is the unknown, so use x for what.
"of" in math usually means a multiplication.
"is" means "="

13% * x = 78

0.13x = 78

x = 78/0.13

x = 600

Answer: the number is 600