a)36 is 75 % of 48
b)18 is 25% of 72
Step-by-step explanation
when we have the percentage and the number , the easiest way to find the value is by applying this formula:

hence
Step 1
a)
what percet of 72 is 18?
let
100 % = 72, ( the number)
x %, = 18
so
replace

therefeore,
18 is 25% of 72
Step 2
b) 36 is 75 % of what,so
let
100%= x=original value
75%=36
so

therefore, 36 is 75 % of 48
I hope this helps you