SSC GD 2023 PYQ — Question 59

SSC GD Constable (English) - 16 Jan 2023 - Shift 2 • Quantitative Aptitude • Q59

A and B together can complete a work in 26 days. A alone can complete it in 52 days. If B works at 50 percent efficiency, then in how many days A and B together will complete the work?

Show answer & explanation

Correct answer: A

Explanation

The correct answer is Option 1 i.e. 104/3 day

A alone can complete the work = 52 days

Therefore

A's daily work rate is 1/52 of the total work

given that

A and B together can complete the work = 26 days

Let's denote B's efficiency = x

Given in the question B works at 50 percent efficiency

B's work rate = 1/2 times that of A's

B's work rate = 1/2 × A's work rate = 1/2 × (1/52) = 1/104 of the total work

Now,

the combined work rate of A and B = A's work rate + B's work rate

Combined work rate = 1/52 + 1/104 = 3/104 of the total work

To find the number of days required for A and B together to complete the work, we can invert the combined work rate

Number of days = 1 / Combined work rate = 1 / (3/104) = 104/3

Therefore, A and B together will complete the work in approximately = (104/3) days