Saved Bookmarks
| 1. |
A alone can complete the work in 10 hours and B alone can complete the work in 15 hours. They both work for 4 hours. After that, both left the work and the remaining work gets completed by C in 12 hours. In what time work will be completed if all three work together?1. 36/7 hours2. 26/17 hours3. 38/12 hours4. 35/11 hours5. 30/19 hours |
|
Answer» Correct Answer - Option 1 : 36/7 hours Given: A's 1 hour's work = 1/10 B's 1 hour's work = 1/15 Calculation: (A + B)'s 1 hour's work = 1/10 + 1/15 = 1/6 (A + B)'s 4 hours work = 4 × 1/6 = 2/3 Remaining work after 4 hours = 1 - 2/3 = 1/3 Now, Time taken to complete 1/3 of work is 12 hours So, time taken to complete 1 work = (12 × 3) hours ⇒ 36 hours Then, (A + B + C) 1 hour's work = 1/10 + 1/15 + 1/36 = 35/180 ⇒ 7/36 ∴ If all worked together, then work will be completed in 36/7 hours |
|