Mark (✓) against the correct answer
12 workers take 4 hours to complete a job. How long would it take 15 workers to complete the job?

(a) 2 hrs 40 min
(b) 3 hrs 12 min
(c) 3 hrs 24 min
(d) 3 hrs 30 min

Open in App

Solution

Time taken by 12 workers to complete the job = 4 h
Time taken by 1 worker to complete the job = $4 \times 12$ h
Time taken by 15 workers to complete the job = $\frac{4 \times 12}{15}$ = 3 h 12 min

Hence, 15 workers will complete the job in 3 h 12 min.

The correct option is (b).

Suggest Corrections

Similar questions

Q. 10 boys can dig a pitch in 12 hours. How long will 8 boys take to do it?
(a) 9 hrs 36 min
(b) 15 hrs
(c) 6 hrs 40 min
(d) 13 hrs 10 min

Q. Tick (✓) the correct answer:
A car takes 2 hours to reach a destination by travelling at 60 km/hr. How long will it take while travelling at 80 km/hr?
(a) 1 hr 30 min
(b) 1 hr 40 min
(c) 2 hrs 40 min
(d) none of these

A car takes 2 hours to reach a destination by travelling at 60 km / hr. How long will it take while travelling at 80 km / hr ?

(a) 1 hr 30 min (b) 1 hr 40 min

Worker A takes 8 hours to do a job. Worker B takes 10 hours to do the same job. How long should it take both A and B, working together but independently, to do the same job?

Q. Tick (✓) the correct answer:
Two pipes can fill a tank in 10 hours and 12 hours respectively, while a third pipe empties the full tank in 20 hours. If all the three pipes operate simultaneously, in how much time will the tank be full?
(a) 7 hrs 15 min
(b) 7 hrs 30 min
(c) 7 hrs 45 min
(d) 8 hrs

Join BYJU'S Learning Program

Mark (✓) against the correct answer 12 workers take 4 hours to complete a job. How long would it take 15 workers to complete the job? (a) 2 hrs 40 min (b) 3 hrs 12 min (c) 3 hrs 24 min (d) 3 hrs 30 min

Time taken by 12 workers to complete the job = 4 h Time taken by 1 worker to complete the job = 4×12 h Time taken by 15 workers to complete the job = 4×1215 = 3 h 12 min Hence, 15 workers will complete the job in 3 h 12 min. The correct option is (b).

Mark (✓) against the correct answer
12 workers take 4 hours to complete a job. How long would it take 15 workers to complete the job?

(a) 2 hrs 40 min
(b) 3 hrs 12 min
(c) 3 hrs 24 min
(d) 3 hrs 30 min

Time taken by 12 workers to complete the job = 4 h
Time taken by 1 worker to complete the job = $4 \times 12$ h
Time taken by 15 workers to complete the job = $\frac{4 \times 12}{15}$ = 3 h 12 min

Hence, 15 workers will complete the job in 3 h 12 min.

The correct option is (b).