If Anil can finish a job in 4 hours and Gustavo can finish

[BTGmoderatorDC]

If Anil can finish a job in 4 hours and Gustavo can finish the same job in 6 hours, how long would it take them, working together at their respective rates, to complete the job?

A. 1 hour, 50 minutes
B. 2 hours, 10 minutes
C. 2 hours, 24 minutes
D. 3 hours, 45 minutes
E. 4 hours, 30 minutes

OA C

Source: Princeton Review

[Ian Stewart]

Anil would do 3 jobs in 12 hours, Gustavo 2 jobs in 12 hours, so together 5 jobs in 12 hours, and thus 1 job in 12/5 hours = 2.4 hours = 2 hours and 24 minutes.

[swerve]

Rate of \(A = \frac{1}{4}\) and rate of \(G= \frac{1}{6}\)

Together they can work at a rate \(= \frac{10}{24}\)

time \(= \frac{24}{10} \cdot 60 = 144\) minutes

or say \(2\) hours, \(24\) minutes. __C__

[Scott@TargetTestPrep]

If Anil can finish a job in 4 hours and Gustavo can finish the same job in 6 hours, how long would it take them, working together at their respective rates, to complete the job?

A. 1 hour, 50 minutes
B. 2 hours, 10 minutes
C. 2 hours, 24 minutes
D. 3 hours, 45 minutes
E. 4 hours, 30 minutes

OA C

Source: Princeton Review

Their combined rate is 1/4 + 1/6 = 6/24 + 4/24 = 10/24 = 5/12. Therefore, when working together, they can finish the job in 1/(5/12) = 12/5 = 2 2/5 hours, i.e., 2 hours and 24 minutes.

Answer: C

[Scott@TargetTestPrep]

If Anil can finish a job in 4 hours and Gustavo can finish the same job in 6 hours, how long would it take them, working together at their respective rates, to complete the job?

A. 1 hour, 50 minutes
B. 2 hours, 10 minutes
C. 2 hours, 24 minutes
D. 3 hours, 45 minutes
E. 4 hours, 30 minutes

OA C

Source: Princeton Review

Their combined rate is 1/4 + 1/6 = 6/24 + 4/24 = 10/24 = 5/12. Therefore, when working together, they can finish the job in 1/(5/12) = 12/5 = 2 2/5 hours, i.e., 2 hours and 24 minutes.

Answer: C