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?

Answer: Option B

Solution

Answer: Option B

Solution:

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