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P is four times as efficient as Q. P can complete a work in 45 days less than Q. If both of them work together, then in how many days the work will be completed?
- A10
- B12
- C15
- D30
Answer not set
Discussion 1
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CCommunity
Let efficiency of Q be q.
⇒ Efficiency of P = 4q.
Time taken by Q = 1/q
Time taken by P = 1/4q
P can complete a work in 45 days less than Q
⇒ 1/4q = 1/q - 45
-3/4q = -45
q = 3/45 = 1/60
Combined efficiency = q + 4q = 5q.
Time taken by them together = 1/5q = 1/(5 × 1/60) = 12 days.
⇒ Efficiency of P = 4q.
Time taken by Q = 1/q
Time taken by P = 1/4q
P can complete a work in 45 days less than Q
⇒ 1/4q = 1/q - 45
-3/4q = -45
q = 3/45 = 1/60
Combined efficiency = q + 4q = 5q.
Time taken by them together = 1/5q = 1/(5 × 1/60) = 12 days.