Answer:
a) The mean is 
b) The standard deviation is 
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
The probability a student selected at random takes at least 55.50 minutes to complete the examination equals 0.6915.
This means that when X = 55.5, Z has a pvalue of 1 - 0.6915 = 0.3085. This means that when 
So




The probability a student selected at random takes no more than 71.52 minutes to complete the examination equals 0.8997.
This means that when X = 71.52, Z has a pvalue of 0.8997. This means that when 
So




Since we also have that 





Question
The mean is 
The standard deviation is 
Answer:
Step-by-step explanation:
Answer:
Width is 2 if that's what you were looking for.
Step-by-step explanation:
I'm guessing it's a rectangle and you want the width?
22-9-9=2w
2w=4
The width is 2
Answer:
51 were the total number of the tickets sold at a school carnival were early-admission tickets.
Step-by-step explanation:
Total number of tickets sold by = 100
Let
be the early-admission tickets sold by the school.
As 51% of the tickets sold at a school carnival were early-admission tickets.
so


Therefore, 51 were the total number of the tickets sold at a school carnival were early-admission tickets.
Answer:
118 cookies
Step-by-step explanation:
1. 9x 16
2.144-26
And then get 118! Have a nice day YW!!!!!???