1. Stem and leaf diagrams

2. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median time taken
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram: 3 4 5 6 7
Completion times
stem
leaf

3. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 7

4. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 7 1

5. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 7 3 1

6. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7
7 3 3 1

7. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 3 1

8. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 3 1

9. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 3
1 8

10. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 3
1 8

11. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 3
1 8 2

12. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7
3 7
1 8 2

13. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7
3 7
1 8 2

14. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7
1 8 2

15. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7
1 8 2

16. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

17. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

18. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

19. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

20. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

21. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

22. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median, quartiles and inter-quartile range
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

23. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

24. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

25. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 2

26. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2

27. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2

28. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2

29. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2

30. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2

31. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2

32. Example - drawing a stem and leaf
Question: students were set a simple task. Their completion times to the nearest second were:
(a) set these data into a stem and leaf diagram
(b) find the median
Answer (a):- (1) key: 4|7 means 47
(2) put values into preliminary diagram:
Completion times 3 4 5 6 7 8 2
(3) re draw diagram with leafs in numerical order:

33. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7

34. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

35. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8 1

36. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8
1 2

37. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

38. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

39. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

40. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

41. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

42. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

43. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

44. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

45. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

46. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

47. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

48. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

49. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

50. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

51. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

52. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8 1

53. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8
1 2

54. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

55. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

56. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

57. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

58. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8 1

59. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8
1 3

60. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

61. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Completion times 3 4 5 6 7 8

62. Example - drawing a stem and leaf
Answer (a):- (3) re draw diagram with leafs in numerical order:
Completion times 3 4 5 6 7 8 2
Don’t forget the key
Completion times
4|7 means 47 3 4 5 6 7 8 2

63. Example - drawing a stem and leaf
Answer (b):-
4|7 means 47
Completion times 3 4 5 6 7 8 2
15th
The median is the middle value:
There are 29 values
i.e. 15th value
Median
= 47

64. Example - drawing a stem and leaf
Answer (b):-
Range = Highest - Lowest
4|7 means 47
Completion times 3 4 5 6 7 8 2
Lowest
Highest
Range = 72 – 38 = 34