Question

Working alone A,B,C can do a piece of work in 11,20 and 55 days respectively.mhow soon can work be done if A is assisted by B and C on alternate days

Answer 1

Work done by A in 1 day = 1/11

Work done by B in 1 day = 1/20

Work done by C in 1 day = 1/55

Work done in 1st day = 1/11+1/20 = 31/220

Work done in 2nd day = 1/11+1/55=6/55

Work done in every two days = 31/220+6/55=1/4

Work done in 8 days =4×1/4=1

i.e., 8 days are required. ANS

Answer 2

A's work in one day = 1/11

B 's work 's in one day = 1/20

C 's work in one day = 1/55

first day work= 1/11+1/20=31/220

second day work= 1/11+1/55=6/55

every two days work = 31/220+6/55=1/4

in 8 days work=4×1/4=1

8 days  ans