Write in an algebraic expression.
5 times a number X is 3 more than x.

5x=3+x

Step-by-step explanation:

5 times X is equal to 5x

3 more than X is equal to 3+x

And we can find this probability using the z table and we got:

Step-by-step explanation:

Let X the random variable that represent the thickness 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 z table and we got: