Ecommerce.com, a large Internet retailer, is studying the lead time (elapsed time between when an order is placed and when it is filled) for a sample of recent orders. The lead times are reported in days.
Lead Time (days) Frequency
0 up to 5........... 6
5 up to 10.......... 7
10 up to 15.......... 12
15 up to 20........... 8
20 up to 25........... 7
Total............. 40
a. How many orders were studied?
b. What is the midpoint of the first class?
c. What are the coordinates of the first class for a frequency polygon?
d. Draw a histogram.
e. Draw a frequency polygon.
f. Interpret the lead times using the two charts.