Robert Bosch Time & Work Quiz-4

Answer: D
Explanation:
Work done by Vinu and Venketesh together in 4+6 (10) days = 10/24 + 10/40 = 2/3
Remaining work = 1 - 2/3 = 1/3
Renuka works for = 1/3 x 30 days = 10 days

Answer: A
Explanation: (Annu + Binod + Chandu)’s 1 day work = 1/8 + 1/10 +1/12 = 37/120
Work done by (Annu + Binod + Chandu) in 2 days = 2 x 37/120
Remaining work = 1 - 37/60 = 23/60
(Binod+Chandu) 1 day work = (1/10 + 1/12) = 11/60
Remaining work will be done by (Binod+Chandu) = 60/11 x 23/60 = 23/11 days ~ 2 days
So, the work will be finished approximately 2 days after Annu had left.i.e., around 4 days.
Hence the answer is 4 days.

Answer: D
Explanation:
Rohan’s 16 hrs work = 16/24 = 2/3
Using Time and Work formula
He will complete all toys in =1/3 x 18 hrs = 6 hrs
Total time = 16 + 6 = 22 hrs.

Answer: B
Explanation:
Let the total work be LCM of 60 and 36 = 180
Efficiency of Aman = 180/60 = 3
Efficiency of Aman + Binod = 180/36 = 5
Efficiency of Binod = 5 - 3 = 2
Combined efficiency of all three = 6
Efficiency of Chandu = 1
So the required ratio of A:B:C = 3:2:1
Hence, the wage of Binod = 2000 Rs

Answer: A
Explanation:
Let the total work be LCM of 15,30,45 = 90
Efficiency of Amandeep = 90/15 = 6
Similarly, Efficiency of Binny and Chitra = 3 and 2
So if they work together, Total time taken to finish the work = \frac{90}{6+3+2} = 90/11
And Total time in which Amandeep can do the work alone = 90/6 = 15 days.

Answer: A
Explanation: 1/15 + 1/30 - 1/60 = 5/60 = 1/12 => 12 minutes

Answer: D
Explanation: Let the pipe B be closed after x minutes.
48/12 – x/32 = 1 => 4 = 1 + x/32
=> x = 96 mins

Answer: D
Explanation: Part filled by (A + B + C) in 5 minutes = 5(1/45 + 1/30 + 1/10) = 7/9
Part filled by C in 5 minutes = 5/10 = 1/2
Required ratio = 1/2 * 7/9 = 7/18 will be the required ratio.

Answer: A
Explanation: Let N be turned off after x minutes. Then,
Part filled by (M + N) in x min. + Part filled by M in (20 – x) min. = 1
Therefore, x(1/30 + 1/60) + (20 – x) = 1
=> x/20 + (20 - x) = 1
=> 19x = 380
=> x = 20

Answer: B
Explanation: Let the efficiency of filling pipes is 5x and 7x respectively.
Efficiency of pipe which empty the tank = 2/3 x 12x/2 = 4x
Total work = 4x * 40 = 160
Time to fill the tank by both the pipes = 160x/12x = 40/3 minutes