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Custom Operation a@b

1000BeginnerAlgebra

AMC 8 · 2010 · Problem 2

If $a @ b = \frac{a\times b}{a+b}$ for $a,b$ positive integers, then what is $5 @ 10$?

Answer choices

A
\frac{3}{10}
B
1
C
2
D
\frac{10}{3}
E
50
0 students attempted0% solvedRating 1000

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