Donna has a 60 miles drive to a work conference. She begins driving at 30 miles per hour, but halfway through the drive, she realizes she is going to be late and speed up. How fast should she drive the remaining distance (in miles per hour) if she needs to complete the entire trip in 90 minutes?
A. 55
B. 60
C. 65
D. 70
E. 88
The OA is B.
We know that the total distance is 60 miles and the total time that she needs to complete the entire trip is 90 minutes or 1.5 hours.
She drove the first 30 miles in an hour because she begins driving at 30 miles per hour, that's mean that the remaining distance is 30 miles.
Then, she will drive the last 30 miles at a rate of, speed = 30 miles / 0.5 hours = 60 miles per hour to complete the trip in 90 minutes.
Is there another strategic approach to solve this PS question? Can any experts help, please? Thanks.
A. 55
B. 60
C. 65
D. 70
E. 88
The OA is B.
We know that the total distance is 60 miles and the total time that she needs to complete the entire trip is 90 minutes or 1.5 hours.
She drove the first 30 miles in an hour because she begins driving at 30 miles per hour, that's mean that the remaining distance is 30 miles.
Then, she will drive the last 30 miles at a rate of, speed = 30 miles / 0.5 hours = 60 miles per hour to complete the trip in 90 minutes.
Is there another strategic approach to solve this PS question? Can any experts help, please? Thanks.
