Question 1
Paper 2Easy6 marksA city council wants to describe the repair times for 240 potholes repaired during April. It selects 12 repair records at random. For these 12 records, the lower quartile is 4 hours and the upper quartile is 8 hours. One recorded repair time is 18 hours.
(a)[2]
State the population and the sample.
(b)[2]
Calculate the interquartile range and determine whether the 18-hour repair time is an outlier.
(c)[2]
The maintenance log confirms that this repair took 18 hours because a lane closure delayed the crew. State whether the value should be removed before describing the sample, giving a reason.