Question

if the average grade of an english class rose from 70 to 85, what is the approximate percent increase?
the percent increase is approximately 14%.
the percent increase is approximately 17%.
the percent increase is approximately 21%.
the percent increase is approximately 35%.

Explanation:

Step1: Recall percent increase formula

The formula for percent increase is $\text{Percent Increase} = \frac{\text{New Value} - \text{Old Value}}{\text{Old Value}} \times 100\%$.

Step2: Identify values

Old value (initial grade) = 70, New value (final grade) = 85.

Step3: Calculate the difference

Difference = $85 - 70 = 15$.

Step4: Apply the formula

$\text{Percent Increase} = \frac{15}{70} \times 100\% \approx 21.43\%$, which is approximately 21%.

Answer:

The percent increase is approximately 21%. (Corresponding to the option: The percent increase is approximately 21%.)