Answer:
The probability that the service desk will have at least 100 customers with returns or exchanges on a randomly selected day is P=0.78.
Step-by-step explanation:
With the weekly average we can estimate the daily average for customers, assuming 7 days a week:
We can model this situation with a Poisson distribution, with parameter λ=108. But because the number of events is large, we use the normal aproximation:
Then we can calculate the z value for x=100:
Now we calculate the probability of x>100 as:
The probability that the service desk will have at least 100 customers with returns or exchanges on a randomly selected day is P=0.78.
Answer:
Milk consumed in 30 days = (30 days)(3.25 litres/day) = 97.5 litres
Step-by-step explanation:
You are given a rate at which the milk is consumed (3.25 litres per 1 day). This is just multiplied by the 30 days to get your answer.
Answer:
The graph in the attached figure
Step-by-step explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form 
or 
In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin
Remember that
The unit rate of change is the same as the slope
so
In this problem
The linear equation is equal to
To graph the line we need two points
we have (0,0) because the line passes through the origin
Determine other point
assume a value of x and calculate the value of y
For x=8
The other point is (8,3)
Plot the points and join them to draw the line
The graph in the attached figure
S = d/t
st = d
t = d/s
The time going is t1.
The time returning is t2.
The total time is 4 hours, so we have t1 + t2 = 4
The speed of the current is c.
The speed going is 9 + c.
The speed returning is 9 - c.
t1 = 16/(9 + c)
t2 = 16/(9 - c)
t1 + t2 = 16/(9 + c) + 16/(9 - c)
4 = 16/(9 - c) + 16/(9 + c)
1 = 4/(9 - c) + 4/(9 + c)
(9 + c)(9 - c) = 4(9 - c) + 4(9 + c)
81 - c^2 = 36 - 4c + 36 + 4c
81 - c^2 = 72
c^2 = 9
c^2 - 9 = 0
(c + 3)(c - 3) = 0
c + 3 = 0 or c - 3 = 0
c = -3 or c = 3
We discard the negative answer, and we get c = 3.
The speed of the current is 3 mph.
Answer:
Step-by-step explanation:
2<y<4
all real numbers >2 and < 4
