Question

Tina lives 30 miles away from her work, and she normally drives at 45 miles per hour. If she wants to reduce her commute time by 10 minutes, how fast should she drive to work, in miles per hour?

a. 54 mph
b. 60 mph
c. 66 mph
d. 72 mph

Answer 1

Tina should drive 60 mph to reduce her commute time by 10 minutes.

Step-by-step explanation:

To find out how fast Tina should drive to reduce her commute time by 10 minutes, we can set up an equation using the formula: distance = speed x time. Tina's original commute time is 30 miles / 45 mph = 2/3 hours, or 40 minutes. She wants to reduce that by 10 minutes, so the new commute time is 30 minutes. Let's denote the new speed she needs to drive as x mph. Therefore, the equation becomes: 30 miles = x mph x 30 minutes. Converting minutes to hours, we get: 30 miles = x mph x 0.5 hours. Solving for x, we find x = 60 mph.