The number of arrivals per minute at a bank located in the central business district of a large city was recorded over a period of 200 minutes, with the following results:
|
Arrivals
|
Frequency
|
|
0
|
14
|
|
1
|
31
|
|
2
|
47
|
|
3
|
41
|
|
4
|
29
|
|
5
|
21
|
|
6
|
10
|
|
7
|
5
|
|
8
|
2
|
a. Compute the expected number of arrivals per minute.
b. Compute the standard deviation.