there r 2 ways to do this type of problem....
(1) 30% of 70...turn percent to decimal...." of " means multiply
0.30(70) = 21.....so 30% of 70 is 21
or
(2) use the percent formula.....is/of = %/100
30% of 70 is what ...
is = x
of = 70
% = 30
is/of = %/100
sub
x / 70 = 30 / 100
cross multiply because this is a proportion
(100)(x) = (30)(70)
100x = 2100
x= 2100 / 100
x = 21
** by the way, this percent formula works on many percent problems...u just have to make sure u sub the right numbers in the right places.
either way u choose to do it, u should arrive at the same answer