The proportion of customers needing an oil change who wait 9 minutes or less.

 

The owner of an automobile repair shop studied the waiting times for customers who arrive at the shop for an oil change. The following data with waiting times in minutes were collected over a one-month period.
repairshop.xlsx
Using classes of 0–4, 5–9, and so on, show the following:
The frequency distribution
The relative frequency distribution
The cumulative frequency distribution
The cumulative relative frequency distribution
The proportion of customers needing an oil change who wait 9 minutes or less.