percent means parts out of 100 so 20% means 20/100
short version, longer version below 20%=1/5 30=1/5 5/5 is 5 times of 1/5 500%=5 times number is 500% of 30
longer explanation
30=20/100 of a number 30=2/10 of a number 30=1/5 of a number multiply both sides by 5 150=5/5 of a number 30=1/5 of 150 100% means 1 times 200% =2 times 500%=5 times 150 is 500% of 30
