A certain fraction is equivalent to 2/5. If the numerator of the fraction is increased by 3 and the denominator is doubled, the new fraction is equivalent to 1/3. What is the sum of the numerator and denominator of the original fraction?  Choose the correct answer:
A) 21 / 4
B) 35
C) 28
D) 26
E) 21

Rationale: x / y = 2 / 5 - > 1 ( x + 3 ) / 2 y = 1 / 3 - > 2 divide 1 by 2 : = > 2 x / ( x + 3 ) = 6 / 5 = > 10 x = 6 x + 18 = > x = 3 / 2 = > y = 5 / 2 * 3 / 2 = 15 / 4 so x + y = 21 / 4 the answer is a
Answer: A