# Question: A random sample of individuals who led their own income

A random sample of individuals who led their own income taxes were asked how much time (hours) they spent preparing last year's federal income tax forms.

(a) Estimate the mean.

(b) Estimate the standard deviation.

(c) Do you think the observations would be distributed uniformly within each interval? Why would that matter?

(d) Why do you imagine that un- equal bin sizes (interval widths) were used?

(a) Estimate the mean.

(b) Estimate the standard deviation.

(c) Do you think the observations would be distributed uniformly within each interval? Why would that matter?

(d) Why do you imagine that un- equal bin sizes (interval widths) were used?

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