A, B, C working independently can do a piece of work in 8, 16 and 12 days respectively. A alone works on Monday, B alone works on Tuesday, C alone works on Wednesday; A alone, again works on Thursday and so on. Consider the following statements: 1. The work will be finished on Thursday. 2. The work will be finished in 10 days. Which of the above statements is/are correct?
- A1 OnlyCorrect
- B2 Only
- CBoth 1 and 2
- DNeither 1 nor 2
Explanation
Here's a brief explanation:
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Calculate Total Work and Efficiencies:
- A takes 8 days, B takes 16 days, C takes 12 days.
- The Least Common Multiple (LCM) of 8, 16, 12 is 48 units. This is our total work.
- A's efficiency = 48/8 = 6 units/day
- B's efficiency = 48/16 = 3 units/day
- C's efficiency = 48/12 = 4 units/day
-
Track Work Done Day by Day:
- Day 1 (Monday, A): 6 units. Total = 6
- Day 2 (Tuesday, B): 3 units. Total = 9
- Day 3 (Wednesday, C): 4 units. Total = 13
- Day 4 (Thursday, A): 6 units. Total = 19
- Day 5 (Friday, B): 3 units. Total = 22
- Day 6 (Saturday, C): 4 units. Total = 26
- Day 7 (Sunday, A): 6 units. Total = 32
- Day 8 (Monday, B): 3 units. Total = 35
- Day 9 (Tuesday, C): 4 units. Total = 39
Remaining work = 48 - 39 = 9 units.
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Day 10 (Wednesday, A): A works and does 6 units. Total = 39 + 6 = 45 units.
-
Remaining work = 9 - 6 = 3 units.
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Day 11 (Thursday, B): B works and does 3 units. Total = 45 + 3 = 48 units.
-
Evaluate Statements:
- Statement 1: The work will be finished on Thursday. This is correct. The work is completed on Day 11, which is a Thursday.
- Statement 2: The work will be finished in 10 days. This is incorrect. The work is finished on Day 11.
Therefore, only statement 1 is correct.
The final answer is A) 1 Only.

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