Posted by **Christine** on Thursday, June 30, 2005 at 2:54pm.

If a and b are positive integers and their product is 3 times their sum, what is the value of 1/a + 1/b?

Given that ab = 3(a + b).

From this, ab/3 = a + b.

Dividing through by ab yields 1/a + 1/b = 1/3.