The price of one gallon of milk has increased from $3.24 to $4.05. what is the percentage increase?
15%
20%
25%
80%
81%

Let initial price be = x = 3.24
final price = y = 4.05
Difference = 4.05 - 3.24
= 0.81
Percentage increase = 0.81 / 3.25 × 100
= 25 %

(4.05 - 3.24) / 3.24x 100
0.81 / 3.24...x 100
0.25x 100
25% increase <==