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The number of arrivals per minute at a bank located in the central businessdistrict of a large city was recorded over a period of 200 minutes, with the following results:

Arrivals…………..Frequencies………Probability
0………………………..14…………………..0.07
1………………………..31………………….0.155
2………………………..47………………….0.235
3………………………..41………………….0.205
4………………………..29………………….0.145
5………………………..21………………….0.105
6………………………..10………………….0.05
7…………………………5…………………..0.025
8…………………………2…………………..0.01
Totals…………………200…………………..1

A. Compute the expected number of arrivals per minute.
B. Compute the standard deviation.

The solution assists with computing the expected number of arrivals per minute.