Question (31/50)
A can do a work in 15 days and B in 20 days. If they work on it together for 4 days, then what fraction of work will be left at the end of 4 days ?(A) 1/4
(B) 1/10
(C) 7/15
(D) 8/15
Question (32/50)
A is 30% more efficient than B. How much time will they working together take to complete a job which A alone could have done in 23 days ?(A) 13 Days
(B) 17 Days
(C) 19 Days
(D) 23 Days