We already know that there are 12 sandwiches.
If there are 3 turkey and 5 veggie then there's 8 out of 12 sandwiches that aren't ham.
12 sandwiches - 8 non-ham sandwiches = 4 ham sandwiches
Now we know there are 4/12 ham sandwiches
We need to simplify this now.
4/12 can be divided by 4
4 goes into 4 1 time and 4 goes into 12 3 times making the answer 1/3
1/3 of the sandwiches are ham.
