Reasoning Questions

Question:1

Vijay can complete a work in 15 days. After working for 5 days, he leaves the work. The remaining work is completed by Kanti in 12 days. In how many days can Kanti alone complete the whole work?

(A) 14 days
(B) 18 days
(C) 22 days
(D) 28 days

solution

Vijay can finish the work in 15 days.
⇒ Vijay’s 1-day work = 1/15.
Vijay works for 5 days.
⇒ Work done by Vijay = 5 × (1/15) = 5/15 = 1/3.
Remaining work = 1 − 1/3 = 2/3.
Kanti finishes the remaining 2/3 work in 12 days.
⇒ Kanti’s 1-day work = (2/3) ÷ 12 = (2/3) × (1/12) = 2/36 = 1/18.
Time for Kanti alone to finish whole work = 1 ÷ (1/18) = 18 days.