The amount of time that three secretaries worked on a special project are in the ratio of 1 to 2 to 5...

[AAPL]

Official Guide

The amounts of time that three secretaries worked on a special project are in the ratio of 1 to 2 to 5. If they worked a combined total of 112 hours, how many hours did the secretary who worked the longest spend on the project?

A. 80
B. 70
C. 56
D. 16
E. 14

OA B

[Brent@GMATPrepNow]

Official Guide

The amounts of time that three secretaries worked on a special project are in the ratio of 1 to 2 to 5. If they worked a combined total of 112 hours, how many hours did the secretary who worked the longest spend on the project?

A. 80
B. 70
C. 56
D. 16
E. 14

OA B

The amounts of time that three secretaries worked on a special project are in the ratio of 1 to 2 to 5
1 + 2 + 5 = 8
So the above information is telling us that, for every 8 hours worked, the first secretary worked 1 hour, the second secretary worked 2 hours, and the third secretary worked 5 hours.
In other words, of the 3 secretaries contributed to 1/8, 2/8 and 5/8 of the job.

If they worked a combined total of 112 hours, how many hours did the secretary who worked the longest spend on the project?
The secretary who worked the longest is the one who contributed 5/8 of the job.
Since the job took a total of 112 hours, the number of hours that secretary worked = 5/8 of 112
= 5/8 x 112
= 70 hours

Answer: B

[Scott@TargetTestPrep]

Official Guide

The amounts of time that three secretaries worked on a special project are in the ratio of 1 to 2 to 5. If they worked a combined total of 112 hours, how many hours did the secretary who worked the longest spend on the project?

A. 80
B. 70
C. 56
D. 16
E. 14

OA B

Solution:

The ratio of the amounts of time that the secretaries worked on the project is x : 2x : 5x or a total of 8x.

Since the total number of hours is 112:

8x = 112

x = 14

The secretary who worked the longest worked for 5x = 5(14) = 70 hours.

Answer: B