K can build a wall in 30 days. L can demolish that wall in 60 days. If K and L work on alternate days, when will the wall be completed ?
A) 120 days
B) 119 days
C) 118 days
D) 117 days
Answers
Answered by
2
Answer:
117 Days
Step-by-step explanation:
K work (1st day) = 1/30
L work(2nd day)= -1/60
hence combined work in 2 days= 1/30 - 1/60 =1/60
Both works alternatively, in odd days K work and L work even days.
work in 2 days =1/60 unit
58/60 unit work in 2 x 58 days = 116 days
Remaining work = 1-58/60 = 1/30
Next day, K turn and K will finish remaining 1/30 work
So total days = 116 + 1 = 117.
Similar questions