cool math puzzle

41:12

30:35

34:37

18:55

22:35

17:24

40:24

28:13

00:59

12:56

36:24

12:54

23:42

20:55

27:27

16:40

34:07

47:12

1:00

1:54

12:19

2:56

13:06

10:30

1:05:34

27:12

16:08

42:47

7:29

10:48

11:13

5:12

51:56

2:21

24:35

28:58

22:11

16:15

16:25

18:59

21:09

25:12

12:44

32:50

18:05

18:11

9:08

4:06

37:52

5:48

8:03

42:25

8:10

9:25

15:03

14:45

40:22

6:58

17:41

3:20