sanju09 wrote:What is the fraction X?
I. If 3 is added to both numerator and denominator of the fraction X, the resulting fraction is 40 percent more than the fraction X.
II. The denominator of the fraction X is 1 more than twice the numerator.

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Let X = A/B

(1) (A + 3)/(B + 3) = (A/B) + 40% of (A/B) = 7A/5B implies there is one equation and 2 variables; NOT sufficient.

(2) B = 1 + 2A implies there is one equation and 2 variables; NOT sufficient.

Combining (1) and (2), 5AB + 15B = 7AB + 21A or 2AB + 21A = 15B
2A(1 + 2A) + 21A = 15(1 + 2A)
2A + 4A² + 21A = 15 + 30A
4A² - 7A - 15 = 0
(4A + 5)(A - 3) = 0 implies A = 3 and B = 7, so the fraction = 3/7; SUFFICIENT.

The correct answer is C.