Subtracting Fractions

Question 1:

2 5 - 1 5
1 5

Question 2:

5 10 - 4 10
1 10

Question 3:

6 8 - 3 8
3 8

Question 4:

2 3 - 4 10
8 30 = 4 15

Question 5:

7 15 - 1 4
13 60

Question 6:

9 20 - 1 3
7 60