how to subtract numbers

2:26

18:32

3:08

3:08

37:45

5:06

3:50

3:02

2:46

9:37

8:28

4:04

1:22

19:19

1:41:55

6:46

3:22

8:27

25:10

11:11

5:51

14:25

21:22

11:57

5:09

1:12:19

5:56

7:32

2:18

2:16

14:26

3:49

1:43

1:40

7:36

1:15

4:50

4:30

11:40

3:44