1.  39 persons can repair a road in 12 days, working 5 hours a day. In how many days will 30 persons, working 6 hours a day, complete the work?
A. 10
B. 13
C. 14
D. 15

Answer: Option B

Explanation:

Let the required number of bottles be x.

More machines, More bottles (Direct Proportion)

More minutes, More bottles (Direct Proportion)

Machines 6 : 10 :: 270 : x
Time (in minutes) 1 : 4

6 x 1 x x = 10 x 4 x 270

x = (10 x 4 x 270)
(6)

x = 1800.