A and B each working alone can do a work in 10 and 15 days respectively. They started the work together but B left after sometime and A finished the remaining work in 5 days. After how many days from the start did B leave?

• A's one day's work=1/10
  B's one day's work=1/15
  in 5 days A worked=5/10=1/2
  so,A and B together work 1/2
  (A+B)'s one day's work=1/10+1/15=1/6
  so,B worked=6*1/2=3 days
• 13 years agoHelpfull: Yes(15) No(7)
• let x be the total number of days,
  a & b total efficiency is 1/6 ,but they work for x-5 days,and remaining five days A will be working...hence the equation becomes,
  (x-5)/6+5/10=1
  by solving we get x= 8,
  8-5=3 days
• 10 years agoHelpfull: Yes(5) No(2)