Answer:
P(Z < 2.37) = 0.9911.
Step-by-step explanation:
We are given that Let z denote a random variable that has a standard normal distribution.
Let Z = a random variable
So, Z ~ Standard Normal(0, 1)
As we know that the standard normal distribution has a mean of 0 and variance equal to 1.
Z =
~ N(0,1)
where,
= mean = 0
= standard deviation = 1
Now, the probability that z has a value less than 2.37 is given by = P(Z < 2.37)
P(Z < 2.37) = P(Z <
) = P(Z < 2.37) = 0.9911
The above probability is calculated by looking at the value of x = 2.37 in the z table which has an area of 0.9911.
Answer:
Let X the random variable that represent the heights of a population, and for this case we know the distribution for X is given by:
Where
and
Since the distribution for X is normal then the we know that the distribution for the sample mean
is given by:
And the standard error is given by:

Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the heights of a population, and for this case we know the distribution for X is given by:
Where
and
Since the distribution for X is normal then the we know that the distribution for the sample mean
is given by:
And the standard error is given by:

Answer:
u = 156.25
Step-by-step explanation:
Step 1: Write equation
31.25 = u/5
Step 2: Solve for <em>u</em>
- Multiply both sides by 5: 156.25 = u
- Rewrite: u = 156.25
Step 3: Check
<em>Plug in u to verify it's a solution.</em>
31.25 = 156.25/5
31.25 = 31.25