Explanation

To evaluate the expression 1/2 + 1/3 - 1/4, we need to find a common denominator. The least common multiple of 2, 3, and 4 is 12.

1/2 = 6/12

1/3 = 4/12

1/4 = 3/12

Now, let's add and subtract:

6/12 + 4/12 - 3/12

= (6 + 4 - 3)/12

= 7/12