If Teena is driving at 55 miles per hour and is currently 7.5 miles behind Joe, who is driving at 40 miles per hour in

[BTGmoderatorDC]

If Teena is driving at 55 miles per hour and is currently 7.5 miles behind Joe, who is driving at 40 miles per hour in the same direction then in how many minutes will Teena be 15 miles ahead of Joe?

A. 15
B. 60
C. 75
D. 90
E. 105


OA D

Source: Princeton Review

[swerve]

If Teena is driving at 55 miles per hour and is currently 7.5 miles behind Joe, who is driving at 40 miles per hour in the same direction then in how many minutes will Teena be 15 miles ahead of Joe?

A. 15
B. 60
C. 75
D. 90
E. 105


OA D

Source: Princeton Review

Total distanceTeena has to drive \(= 7.5 + 15 =22.5\) miles

relative speed \(=55-40=15\) miles per hour

Time taken by her to reach \(15\) miles ahead of Joe \(= \dfrac{22.5}{15}=\dfrac{3}{2}=1.5\) hours \(=90\) minutes

[Scott@TargetTestPrep]

If Teena is driving at 55 miles per hour and is currently 7.5 miles behind Joe, who is driving at 40 miles per hour in the same direction then in how many minutes will Teena be 15 miles ahead of Joe?

A. 15
B. 60
C. 75
D. 90
E. 105


OA D

Solution:

In order for Teena to go from 7.5 miles behind Joe to 15 miles ahead of him, she must travel 7.5 + 15 = 22.5 miles more than Joe. Therefore, we can create the equation when t is the number of hours it takes Teena to accomplish that feat:

40t + 22.5 = 55t

22.5 = 15t

1.5 = t

We see that it takes 1.5 hours or 90 minutes for Teena to go from 7.5 miles behind Joe to 15 miles ahead of him.

Answer: D