SAT Math Question of the Day

Q: If 5/2y = a/a+b, what is y in terms of a and b?

1. 2(a+b)/5b
2. 2(a+b)/5a
3. 2a/5(a+b)
4. 5a/2(a+b)
5. 5(a+b)/2a

UNANSWERED.

The correct answer is E.

A: 5(a+b)/2a is the right answer.

5/2y = a/a+b
Cross-multiply
5 × (a+b) = 2y × a
2ay = 5(a+b)
y = 5(a+b)/2a