Question

P can complete a work in 12 days working 8 hours a day. Q can complete the same work in 8 days working 10 hours a day. If both P and Q work together, working 8 hours a day, in how many days can they complete the work?

• A.
• B.
• C.
• D.
• E. 7

Answer 1

The correct option is A

P can complete the work in $12\times 8$ hrs. = 96 hrs

Q can complete the work in $8\times 10$ hrs. = 80 hrs
∴ P’s 1 hour’s work = $\frac{1}{96}$ and Q’s 1 hours work = $\frac{1}{80}$

Work done in one hour = $\frac{11}{480}$

Work done in 8 hours = $\frac{11}{60}$

Complete work will be done in $\frac{60}{11}days.$