Answer :
percent formula : is/of = %/100
18 is what percent of 20...
is = 18
of = 20
% = x
sub and solve
18/20 = x/100
cross multiply
(20)(x) = (100)(18)
20x = 1800
x = 1800/20
x = 90 <=== so 18 is 90% of 20
18 is what percent of 20...
is = 18
of = 20
% = x
sub and solve
18/20 = x/100
cross multiply
(20)(x) = (100)(18)
20x = 1800
x = 1800/20
x = 90 <=== so 18 is 90% of 20