The probability the 51st call arriaves within 150hours is 0.0431, the probability the next call arrives within the next 2 hours 0.5488, the probability the sum of these 50 numbers is less than 356 is 0.4165.
Data;
Using poission formula,
Let's substitute the values into the formula.
For 50 calls in 150 hours
For 150 hours = x = 0.3 * 150 = 45
b)
The probability the next call arrives after 2 hours.
c)
The number of calls recieved each day is recorded for 50 consecutive days.
for 50 days;
The mean = 360
The standard deviation is given as
The probability the sum of these 50 number is less than 356 is
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