Question
'Amit', 'Ravi', and 'Neha' can finish a piece of work in
66, 99, and 132 days respectively. They all started the work, but Amit left 8 days before the work ended and Ravi left 4 days before. Find total days to complete the work. (Calculate approximate value)Solution
ATQ,
Let the total work be 1188 units (LCM of 66, 99, 132)
Efficiency of Amit = 1188 / 66 = 18 units/day
Efficiency of Ravi = 1188 / 99 = 12 units/day
Efficiency of Neha = 1188 / 132 = 9 units/day
Let total time = n days
(18 + 12 + 9)(n - 8) + (12 + 9)(4) + 9(4) = 1188
Or, 39n - 312 + 84 + 36 = 1188
Or, 39n = 1380
So, n = 1380 / 39 = 35.38 ≈ 35 days
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