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Manish is four times as efficient as Puneet. Manish takes 90 days less than Puneet to complete a book. If both of them work together, then in how many days the book will be completed?
- A28
- B25
- C24
- D30
Answer not set
Discussion 1
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CCommunity
Let Puneet complete the book = a days
So, Manish complete the book = 4a days
Difference of days = 4a – a = 3a = 90 days
⇒ a = 30 days
Time taken by Puneet = a = 30 days
Time taken by Manish = 4a = 120 days
Let Total work = Lcm of 30 and 120 = 120 units
Efficiency of Puneet = 120/30 = 4 units/day
Efficiency of Manish = 120/120 = 1 unit/day
Total Efficiency of Puneet and Manish = 4 + 1 = 5 units/day
∴ Total time taken to complete the book = 120/5 = 24 days
So, Manish complete the book = 4a days
Difference of days = 4a – a = 3a = 90 days
⇒ a = 30 days
Time taken by Puneet = a = 30 days
Time taken by Manish = 4a = 120 days
Let Total work = Lcm of 30 and 120 = 120 units
Efficiency of Puneet = 120/30 = 4 units/day
Efficiency of Manish = 120/120 = 1 unit/day
Total Efficiency of Puneet and Manish = 4 + 1 = 5 units/day
∴ Total time taken to complete the book = 120/5 = 24 days