A can do a certain job in 25 days which B alone can do in 20 days. A started the work and was joined by B after 10 days. The number of days taken in completing the wotk were ?	Answers
A) 14 2/3kmph  B) 15 2/3kmph  C) 16 2/3kmph  D) 17 2/3kmph  E) 18 2/3kmph
Explanation:   Work done by A in l0 days = (1/25) *10 = 2/5   Remaining work = 1 - (2/5) = 3/5   (A+B)s 1 days work = (1/25) + (1/20) = 9/100   9/100 work is done by them in 1 day.   hence 3/5 work will be done by them in (3/5)*(100/9)   = 20/3days.   Total time taken = (10 + 20/3) = 16*(2/3) days   Option 16 2/3kmph
<result>C</result>
A can do a certain job in 25 days which B alone can do in 20 days. A started the work and was joined by B after 10 days. The number of days taken in completing the wotk were ?