A work is done by P & Q, Q & R, and R & P in 12, 15, and 20 days, respectively. How many days will P alone take to complete the work?
Answer & explanation
Correct answer: option 4
P + Q = 12 days,
Q + R = 15 days,
R + P = 20 days,
⇒ Adding all the efficiencies, we get,
⇒ 2(P + Q + R) = 12
⇒ P + Q + R = 6,
Therefore P = 2 (Efficiency)
⇒ Time taken by P to complete the total work = \(\frac{60}{2}\) = 30 days.
..(\(\frac{Work}{Efficiency}\) = Time)