SSC CGL 2019 PYQ — Question 53

SSC CGL - 7th June 2019 - Shift 1 • Quantitative Aptitude • Q53

Three numbers are such that if the average of any two of them is added to the third number, the sums obtained are 164, 158 and 132 respectively. What is the average of the original three numbers?

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e. 

Let numbers are a, b and c:

Given

(a + b)/2 + c = 164

(b + c)/2 + a = 158

(a + c)/2 + b = 132

Given equations can be converted as:

a + b + 2c = 328 ---- (1)

b + c + 2a = 316 ---- (2)

c + a + 2b = 264 ---- (3)

Adding all equations:

4(a + b + c) = 908

(a + b + c) = 908/4 = 227

From equation 1, 2 and 3:

c = 101, a = 89, b = 37

Average of the original three numbers= (101 + 89 + 37)/3 = 227/3 =