Question 1

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	12
1	31
2	43
3	45
4	29
5	21
6	8
7	7
8	4

1. Compute the expected number of arrivals per minute.
2. Compute the standard deviation.