Answer:
2.5%
Step-by-step explanation:
part over whole = part over whole
0.5/20 = p/100
then cross multiply
(0.5)(100) = 20p
50 = 20p
then divide both sides by 20
2.5 = p
To check, change 2.5% to a decimal by dividing by 100, (=0.025) then multiply by 20.
20 x 0.025 = 0.5
