You didn’t post the options but that is also equal to 1.0 x 10^-6
Answer:
And we can find this probability using the normal standard table or excel:
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 amount of ml of a population, and for this case we know the distribution for X is given by:
Where and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability using the normal standard table or excel:
9. Let x equal the number
Two less than a number is
x - 2
Is more than 15 is
> 15
Put them together for
x-2 > 15
Now solve
x-2 > 15
x > 17
10. Let x equal a number
Seven more than a number is
x+ 7
Is less than or equal to 27 is
<= 27
Put them together for
x + 7 <= 27
Now solve
x+ 7 <= 27
x <= 20