Data analysis

Classify by scale: (a) the colour of a car, (b) a pupil’s rank in the class, (c) the temperature in °C, (d) the length of a journey in minutes.

Find the mean, median and mode of 3, 4, 4, 6, 8, 9, 10, 10 (mean first; list is already sorted).

Find the variance and the standard deviation of 1, 5 (mean 3, divide by 2).

Using mark = 6 × hours + 41, predict the mark for 5 hours. Is the prediction reliable for 5 hours? And for 20 hours?

In a school, the number of umbrellas brought and the number of colds both rise in winter. Does this prove that umbrellas cause colds? Explain in a sentence.