QuestionAl surveyed 60 people on restaurant spending.
a) Identify the modal class.
b) Estimate the mean.
c) Estimate the standard deviation and discuss it.
d) Estimate the variance, range, and interquartile range, explaining why they are estimates.

Studdy Solution
These are all estimates because we do not know the exact values of the data, only the class intervals. The mid-points, standard deviation, variance, range and interquartile range are all based on these class intervals, so they are only estimates of the true values.