Manipulate the first equation to
y = 22-7z
Then substitute in the second to find z
8(22-7z) + 7z = 127
176-56z+7z = 127
-49z = -49
z = 1
So y = 22-7(1) = 22-7 = 15
y = 15; z = 1
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;
- Mean rate = 0.3
- x = 50
- standard deviation = ?
<h3>Poission Rule</h3>
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

Learn more on poission formula here;
brainly.com/question/7879375
Answer:
D
Step-by-step explanation:
because All Of The Value Of X Is The Same
Y = 85
the fraction is 85/45