To first find the answer to this, let's find a common denominator between each fraction. The denominator is the bottom number of a fraction.
To find the common denominator, let's factor out each of our denominators 5 times to see if they have a common number.
4: 4, 8, 12, 16, 20
2: 2, 4, 6, 8, 10
They both appear to have the smallest common denominator of 4, so let's use 4.
We already have 1/4 with a denominator of 4, but not 1/2.
2 x 2 = 4, so multiply the numerator and the denominator of 1/2 by 2.
1 x 2 = 2
2 x 2 = 4
Your new fraction is 2/4.
Our expression now is:
-2 1/4 + 5 2/4
or (in simpler terms)
5 2/4 - 2 1/4
Subtract the fractions first.
2/4 - 1/4 = 1/4
Now subtract the whole numbers.
5 - 2 = 3
You are left with:
3 1/4
I hope this helps!