The probability model in the following table describes the number of repair calls that an appliance repair shop may receive during an hour. Complete parts a and b.
Repair Calls
2
Probability
0.2
0
0.1
1
0.5
+
3
0.2
a) How many calls should the shop expect per hour?
The shop should expect 1.5 calls per hour.
(Round to two decimal places as needed.)
b) What is the standard deviation?
The standard deviation is
(Round to two decimal places as needed.)
