Math Multiple Choice

If symbol is defined for all positive numbers a and b by a symbol b = a times b over a plus b , then
10 symbol 2 =

(A) CORRECT ANSWER
(B)
(C) 5
(D)
(E) 20

Explanation:

Substituting 10 for a and 2 for b in the expression a times b over a plus b yields equation
The correct answer is (A).

(from the October 18, 1997 test)