Answer
The rate of the discount is 20%.
Work Step by Step
Let r represent the rate of the discount.
A guideline for this problem would be:
Original selling price - Discount = Discount sale price
So, 40 - r $\times$ 40 = 32
40 - 40r = 32
40 - 32 = 40r
8 = 40r
Divide both sides by 40:
0.2 = r
Multiply the result by 100% to convert it to a percentage.
0.2 $\times$ 100% = 20%
The rate of the discount is 20%.
