Q4 Answer of Timed Quant Practice - Medium Section 1 Sample #5

GRE Quant Problem Solving
1

prb1

Why is the answer A and not D?

(x+1/x)^2 = x^2 + 2 + (1/x)^2
(x+1/x)^2 = x^2 + (1/x)^2 + 2
(x+1/x)^2 = 7 + 2
(x+1/x)^2 = 9

Taking Square root
Either, x+1/x = 3
or, x+1/x = -3

2

Hint: x is positive.

3

Thanks. Got it Now.