X can do a work in 3 days, Y does three times the same work in 8 days, and Z does five times the same work in 12 days. If they have to work together for 6 hours in a day, then in how much time can they complete the work?

A. 4 hours

B. 5 hours 20 minutes

C. 4 hours 10 minutes

D. 5 hours

Answer: Option B

Solution (By Examveda Team)

$$\eqalign{ & {\text{So, required answer}} \cr & = \left( {\frac{{24}}{{8 + 9 + 10}}} \right) \times 6{\text{ hr/day}} \cr & = \frac{{48}}{9} \cr & = \frac{{16}}{3} \cr & = 5{\text{ hr }}20\,\min \cr} $$