Explanation:
A percent is 1 part out of of 100.
Find what percentage 18 is of 72. The part is 18.
The whole is 72.
Let n represent the percent.
Write a proportion to solve for n.
18
72
=
n
100
18 x 100 = 72n
1,800 = 72n
1,800 ÷ 72 = 72n ÷ 72
25 = n
25% of the cookies were gingerbread.
