Answer:
171 newspapers.
Step-by-step explanation:
Problems of normally distributed samples are 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.
In this problem, we have that:

How many newspapers should the newsstand operator order to ensure that he runs short on no more than 20% of days
The number of newspapers must be on the 100-20 = 80th percentile. So this value if X when Z has a pvalue of 0.8. So X when Z = 0.84.




So 171 newspapers.
<u>I'll assume you need to find the equation of the line that passes through those points.</u>
Answer:

Step-by-step explanation:
<u>Equation of a Line:</u>
The equation of a line passing through points (x1,y1) and (x2,y2) can be found as follows:

The given points are (-4,2) and (12,6), thus:

Operating:

Simplifying, the equation in point-slope form is:

Answer:
x = 40°
Step-by-step explanation:
Given that ∠SRT ≅ ∠STR
Then ∠STR = 20
∠STR and ∠STU are what you call supplementary angles. This means that the sum of their measurements is equal to 180° because they form a straight line.
So if:
∠STR + ∠STU = 180°
m∠STU = 4x
m∠STR = 20
Then:
4x + 20° = 180°
Now we solve for x:

x = 40°