Using z-scores, it is found that the value of z is z = 1.96.
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Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula, which for a measure X, in a distribution with mean 
and standard deviation 
, is given by:
- It measures how many standard deviations the measure is from the mean.
- Each z-score has an associated p-value, which is the percentile.
- The normal distribution is symmetric, which means that the middle 95% is between the <u>2.5th percentile and the 97.5th percentile</u>.
- The 2.5th percentile is Z with a p-value of 0.025, thus Z = -1.96.
- The 97.5th percentile is Z with a p-value of 0.975, thus Z = 1.96.
- Thus, the value of Z is 1.96.
A similar problem is given at brainly.com/question/16965597
Answer:
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Step-by-step explanation:
We have been given that 4 days I have 140 copies of a book, 9 days I only have 50 left. We are asked to write an equation 
, where c is number of copies still on hand and t days being available.
We have two points on line (4,140) and (9,50). Now, we will use these points to find slope as:
Now, we will use point-slope form of equation 
and substitute and coordinates of point (9,50) as:
Therefore, our required equation would be .
c c a a are the right answers just took it
For this case we must factor the following polynomial:
We can take common factor x:
To factor the expression within the parenthesis, we must find two numbers that when multiplied give 49 and when added together, 14 are obtained. These are: 7 and 7.
Thus, the expression is factored as:
Answer:
