IBPS PO Prelims Model Paper 1 with solutions

Condition 1- A is twice as fast as B, means their ratio is 2 : 1.
Condition 2- B is one third as fast as C, means their ratio is 1 : 3.
Then we can say the ratio of A, B and C is as follows:
According to condition 1: A : B = 2 : 1
According to condition 2 : B : C = 1 : 3
Thus, ratio of A : B : C = 2 : 1 : 3
This ratio denotes the working efficiencies of A, B and C, which means:
A, B and C can do = (2 + 1 + 3 = 6) work/day
Now, we can calculate the total work, i.e.:
Total work = Total days × Per day work
Total work = 30 × 6 = 180
A can do the same work in: = (Total work ÷ Efficiency of A) = 180 ÷ 2 = 90 days
B can do the same work in: = (Total work ÷ Efficiency of B) = 180 ÷ 1 = 180 days
C can do the same work in: = (Total work ÷ Efficiency of C) = 180 ÷ 3 = 60 days
Thus, A, B and C can individually complete the same work in 90, 180 and 60 days, respectively.