The original number of students in a class is 40, and now there are 32. What is the percent decrease in the number of students?

Question

A
18%
B
30%
C
25%
D
20%

Answer 1

To calculate the percent decrease in the number of students, you can use the following formula:

\[ \text{Percent Decrease} = \left( \frac{\text{Original Value} - \text{New Value}}{\text{Original Value}} \right) \times 100 \]

In this case, the original value is 40 and the new value is 32.

1. Calculate the decrease in the number of students: \[ \text{Decrease} = 40 - 32 = 8 \]

2. Now plug the values into the formula: \[ \text{Percent Decrease} = \left( \frac{8}{40} \right) \times 100 \]

3. Calculate the fraction: \[ \frac{8}{40} = 0.2 \]

4. Now multiply by 100 to get the percentage: \[ 0.2 \times 100 = 20% \]

Therefore, the percent decrease in the number of students is 20%.

The answer is D: 20%.