1 19/20

Explanation

4 1/5-2 1/4=N

LCD:

5,10,15,20

4,8,12,16,20

4 4/20-2 5/20=1 19/20

Answer:

4 1/5 - 2 1/4

= 21/5 -9/4

= 39/20 or 1 19/20