Answer:


And using a calculator, excel ir the normal standard table we have that:

And we can calculate the probability like this:
Step-by-step explanation:
A random sample of 36 observations has been drawn from a normal distribution with mean 50 and standard deviation 12. Find the probability that the sample mean is in the interval 47<=X<53. Is the assumption of normality important. Why?
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 variable of interest 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 we know that the distribution for the sample mean
is given by:

We can find the probability required like this:


And using a calculator, excel ir the normal standard table we have that:

And we can calculate the probability like this:

Answer:
The mom is 5 feet 3 inches
Step-by-step explanation:
<u>Step 1: Make an equation</u>
m = 1 3/4 * 3
<u>Step 2: Solve</u>
m = (4/4+3/4) * 3
m = 7/4 * 3
m = 21/4
m = 5.25
<em>m = 5 feet 3 inches</em>
<em />
Answer: The mom is 5 feet 3 inches
5x=25 could be one.
25/x-3=2 is another.
And the last one could be x/85+7=24
The turtle is 3 feet below the surface of the sea, if it rises 3 feet, it will be even with sea level. So, 0 can be represented as sea level.