| Date | May 2009 | Marks available | 2 | Reference code | 09M.1.sl.TZ1.1 |
| Level | SL only | Paper | 1 | Time zone | TZ1 |
| Command term | Calculate | Question number | 1 | Adapted from | N/A |
Question
Eight houses in a street are inhabited by different numbers of people, as shown in the table below.
The following statements refer to the number of inhabitants per house. Write down true (T) or false (F) for each.
The mean is \(5\).
The range is \(4\).
The mode is \(6\).
The standard deviation is \(1.4\) correct to \(2\) significant figures.
Calculate the interquartile range for the number of inhabitants per house.
Markscheme
F (A1)
[1 mark]
T (A1)
[1 mark]
F (A1)
[1 mark]
F (A1) (C4)
[1 mark]
IQR = 6 − 4 (M1)
Note: Award (M1) for identifying correct quartiles.
IQR = 2 (A1)(ft) (C2)
[2 marks]
Examiners report
It was expected that candidates would use the GDC for this question.
It was expected that candidates would use the GDC for this question.
It was expected that candidates would use the GDC for this question.
It was expected that candidates would use the GDC for this question.
It was pleasing to note that most candidates were able to choose the appropriate standard deviation.
It was expected that candidates would use the GDC for this question.
A common error was writing the IQR as an interval.
