Question

If 22.5% is 18 how do I found out what 37.5% is

Answer 1

you can use proportions.

22.5/100 = 18/x
cross multiply:
100 x 18 = 1800
1800/22.5 = 80

so now you know 80 is the 100%.
then do:

37.5/100 = x/80
cross multiply:
37.5 x 80 = 3000
3000/100 = 30

37.5% = 30