Answer:
E 0.923
Step-by-step explanation:
The Z score is a measurement used in statistics to determine the relationship between a value and a mean of a group of values measured as standard deviation from the mean. The z score (z) is given as:
, Where μ is the mean, σ is the standard deviation and x is the value.
Given that:
σ = 7, μ = 80 and x = 90
From the normal distribution table, P(X < 90) = P(z < 1.43) = 0.923
To determine the system of inequality that has been graphed, we need to be very smart.
Observe that all the equations are the same.
Also note that all the lines are solid. This should tell you that the inequities should involve.
Therefore the answer is between option A and B.
So we choose a point in the solution region to discriminate between A and B.
Let us choose the origin since that is easy to evaluate.
We substitute into option A to get.
The above statements are false
We now substitute into option B
Both statements are true, therefore the correct answer is option B.