25 men reap the field in 20 days
∴ 10 men can reap the feild in (20 x 25)/ 10 = 50 days.
When 15 men leave the work, 10 men remain and they can reap in 37¹/₂ days
= (37¹/₂)/ 50 = 3/4 of the field

Correct Option: C

25 men reap the field in 20 days
∴ 10 men can reap the feild in (20 x 25)/ 10 = 50 days.
When 15 men leave the work, 10 men remain and they can reap in 37¹/₂ days
= (37¹/₂)/ 50 = 3/4 of the field
Hence, all men must work till (1 - 3/4) = 1/4 of the field is reaped in 20/4 = 5 days.

∵ (1/5 + 1/9 + 1/15) = 17/45 work is finished in 1 hour
∴ Remaining work = 1 - 17/45 = 28/45
⇒ (A + B)'s 1 hour's work = 1/5 + 1/9 = 14/45

Correct Option: A

∵ (1/5 + 1/9 + 1/15) = 17/45 work is finished in 1 hour
∴ Remaining work = 1 - 17/45 = 28/45
⇒ (A + B)'s 1 hour's work = 1/5 + 1/9 = 14/45
14/45 work is done by (A and B) in 1 hour
28/45 work will be done by A and B in (45/14) x (28/45) = 2 hours

∵ C's 1 day's work
= [( A + B + C)'s 1 day's work] - [(A + B)'s 1 day's work]
= [1/8 - (1/24 + 1/16)] = (1/8 - 5/48) = 1/48

Correct Option: D

∵ C's 1 day's work
= [( A + B + C)'s 1 day's work] - [(A + B)'s 1 day's work]
= [1/8 - (1/24 + 1/16)] = (1/8 - 5/48) = 1/48
∴ C alone can do it in 48 days.

1 day work of A = 1/10 = 0.1
1 day work of B = 1/10 + 60% of 1/10 = 0.1 + 0.06 = 0.16

Correct Option: C

1 day work of A = 1/10 = 0.1
1 day work of B = 1/10 + 60% of 1/10 = 0.1 + 0.06 = 0.16
So number of days taken by B to complete the work = 1/0.16
= 6²/₃

∵ B's daily earning = Rs. (150 - 94) = Rs. 56
⇒ A's daily earning = Rs. (150 - 76) = Rs. 74

Correct Option: D

∵ B's daily earning = Rs. (150 - 94) = Rs. 56
⇒ A's daily earning = Rs. (150 - 76) = Rs. 74
∴ C's daily earning = Rs. [(150 - (56 + 74)] = Rs. 20