Math question, Algebra I Equations?!?

Question

2/3a - 1/5a = 2

The answer is either 2 or 30/7, but I have no idea which! I got two using the finding LCD and multiplying the fractions, and I got 30/7 when I plugged the two fractions in the calculator to combine like terms and then divided the result by two and reached 30/7. Which is it?

Answer 1

(2/3)a - (1/5)a = 2

Multiply both sides by the common denominator of 15.

10a - 3a = 30

7a = 30

a = 30/7