Saved Bookmarks
| 1. |
A can do a piece of work in 7 days of 9 hours each and B can do it in 6 days of 7 hours each.How long will they take to do it, working together 8 2/5 hours a day? |
|
Answer» Answer: For A in 1 day, he can do 1/7 of WORK in 9 HR, he can do 1/7 of work in 1 hr, he can do 1/63 of work in 8 2/5 hr, he can do (1/63)(42/5) = 0.1333 of work For B in 1 day, he can do 1/6 of work in 7 hr, he can do 1/6 of work in 1 hr, he can do 1/42 of work in 8 2/5 hr, he can do (1/42)(42/5) = 0.2 of work. when they work together 0.1333+0.2= 0.3333 of work in a day. to COMPLETE the whole work, i,e 0.3333(1/0.3333) so in 1/0.3333 days whole work will complete i,e in 3 days whole work will complete. So, they will take 3 days to complete the work. |
|