Question

In june, Mr chen's students read 40 books. in july the read 30 books. what is the percent increase or decrease in the number of books they read?

A. 20% increase
B. 25% decrease
C. 20% decrease
D. 40% decrease

Answer 1

To calculate the percent increase or decrease, find the difference between the two values and divide it by the original value, then multiply by 100.

Step-by-step explanation:

To calculate the percent increase or decrease, we need to find the difference between the number of books read in June and July and then express it as a percentage of the original value.

The number of books read in June is 40, and in July it is 30. The difference is 40 - 30 = 10.

To find the percent increase or decrease, we divide the difference (10) by the original value (40) and multiply by 100.

The calculation is (10/40) * 100 = 25%.

Therefore, the correct answer is B. 25% decrease.