First and last of all, you don't subtract them while they are still mixed fractions with UNEQUAL DENOMINATORS.
To make same denominators, we need to find the Least Common Multiple(LCM).
The LCM of 2 and 3 is 6.
So you multiply 1/2 by 3/3 to get a denominator of 6, and multiply 1/3 by 2/2 to get a denominator of 6.
1/2 x 3/3 = 3/6
1/3 x 2/2 = 2/6
4 3/6 - 1 2/6
The whole number minus whole number, and fraction minus fraction.
[tex]3 \frac{1}{6} [/tex]
