Answer:
C. 25%
Step-by-step explanation:
percent change = (new number - old number)/(old number) * 100%
The new number is the increased time, 75 minutes, and the old number is the original time, 60 minutes.
percent change = (75 min - 60 min)/(60 min) * 100%
percent change = (15 min)/(60 min) * 100%
percent change = 0.25 * 100%
percent change = 25%
Since the percent change is a positive number, it is a percent increase.
The percent increase was 25%.
Answer: C. 25%