However, when they work together, they do 25% more work than is expected. If they work for a few days alone and for few days together (both being integers only), then the

work could not have been completed in exactly

A. 10 days

B 14 days

C. 16 days

D. 17 days

E. either none or at least 2 of these

job alone?

A. 8

В. 12

C. 18

D 20]]>

Raju can do the work in 10 days so he does 60/10 = 6 units / day

similarly Vicky does 5 units/ day and

Tinku does 4 units per day

Raju left the work after 2 days so work done by Raju , Vicky and Tinku in first two days = ( 6 + 5 + 4) x 2 = 30 units

Vicky left the work 3 days before its completion , so Tinku alone does : 4 x 3 = 12 units

So remaining ( 60 - 30 - 12) = 18 units work was done by Vicky and Tinku so 18/ ( 4+5) = 2 days

So total days : 2 + 2 + 3 = 7 days.

Time taken by A to do the work : x days

so time taken by B: 2x days

work done by A in 1 day : 1/x units

Work done by B in 1 day : 1/2x units

Work done by A and B in 1 day = 1/7 units

So, 1/x + 1/2x = 1/7

Solving this we get x = 21/2

So A alone takes 21/2 days .]]>

B=144/24=6

C=144/36=-4 (negative because it empties tank )

since A works from 8 to 1 means he work for 5 hours and and B works from 10 to 1 means for 3 hours and then C starts with A and B

5*8 + 6*3 + (8+6-4)t= 144

t=8 hours 36 min

time after 1:00= 9:36 (answer)

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