Answer:

Step-by-step explanation:
Z-score:
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.
In this question:

You listen to the radio station for 1 hour, at a randomly selected time, and carefully observe that the amount of advertising time is equal to 17 minutes. Calculate the z-score for this amount of advertising time.
We have to find Z when X = 17. So



The answer is between 45,000,000-65,000,000
Second side= x
First side = 2x
Third side = x+5
x+2x+x+5=49
4x=44
x=11
1st side= 22
2nd side = 11
3rd side = 16
The answer would be 13 1/2 because you turn the 12 into a fraction then change the division sign into a multiplication sign and find the reciprocal of 8/9 which is 9/8 you could now divide 12/1 divided by 9/8 you could cross simply then dove to get 27/2 and in the end you get 13 1/2 if you turn the improper fraction into a mixed number.