2.5, because 6 2/3 - 4 1/6....
First, find the most common denominator! Which is 6.
Multiply the bottom term to 2 times. (To get 6.) Now do the same for the top! So 6 4/6 - 4 1/6
Second, you subtract!
2 3/6
Third, if your teacher has ever taught you this or not....
If she did: Simply 2 3/6 into 2 1/2!
Finally,
2 1/2 can be 2.5, 2 3/6, or just 2 1/2!