Stage 8 - Q1 - 2 marks
For value 47 in a tens-and-units stem-and-leaf diagram, give the stem and leaf.
Hint
Separate the tens and units.
Stage 8 - Q2 - 2 marks
How should 30 appear in a tens-and-units stem-and-leaf diagram?
Hint
Do not omit a zero leaf.
Stage 8 - Q3 - 3 marks
Draw an ordered stem-and-leaf diagram for 12, 15, 17, 21, 24 minutes. Include a key.
Hint
The key must identify both value and unit.
Stage 8 - Q4 - 3 marks
Draw an ordered diagram for 19, 21, 21, 24, 30, 30 minutes.
Hint
One leaf represents one observation.
Stage 8 - Q5 - 4 marks
Draw an ordered stem-and-leaf diagram for 23, 12, 35, 21, 12, 30, 28, 35 minutes.
Hint
Check that the number of leaves equals the number of original data values.
Stage 8 - Q6 - 4 marks
Add 27 minutes to the diagram and redraw the ordered leaves. State the new number of observations.
Hint
Keep the existing observations and their multiplicities.
Stage 8 - Q7 - 4 marks
Draw a diagram with consecutive stems for 12, 17, 31, 34 minutes. Explain why stem 2 is empty.
Hint
Include a stem for the missing tens interval.
Stage 8 - Q8 - 4 marks
A diagram lists stem 2 with leaves 1, 4, 8. One key says 2|1 means 21 cm; another says 2|1 means 2.1 m. Explain why a key is essential and list the three values under each key.
Hint
Digits alone do not specify the measurement scale.
Stage 8 - Q9 - 5 marks
A learner draws stem 1 leaves 2, 8 and stem 2 leaves 7, 1, 7 for data 12, 18, 21, 27, 27. Repair the diagram and explain which part is wrong.
Hint
Distinguish a missing value from an ordering error.
Stage 8 - Q10 - 6 marks
Create six two-digit integers with mean 25, median 25 and range 18, using exactly two values in each of the teens, twenties and thirties. Draw an ordered stem-and-leaf diagram and verify every condition.
Hint
Choose extremes with the required gap, then balance the middle pairs around 25.