Answer:
Step-by-step explanation:
The standard deviation is the square root of the variance, and the variance is found by using the mean. So we will do that first. I will use the population variance as opposed to the sample variance since our set of numbers is small.
The mean: 8 + 12 + 15 + 17 + 18 = 70 and divide that by 5 to get
and use this to find the variance in the formula:
it is a bit difficult to enter that formula in correctly, but here's how it works mathematically:

Squaring this ensures us that we don't end up with zero, which would be useless.
so
which means that the standard deviation is
s = 3.633
(If you do it with n-1 = 4 in the denominator of the variance, you get a standard deviation of 4.062)
Answer:
I mean it would just be q(x) = 0
Step-by-step explanation:
Answer:
We know that n = 50 and p =0.78.
We need to check the conditions in order to use the normal approximation.
Since both conditions are satisfied we can use the normal approximation and the distribution for the proportion is given by:

With the following parameters:


Step-by-step explanation:
Previous concepts
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
Solution to the problem
We know that n = 50 and p =0.78.
We need to check the conditions in order to use the normal approximation.
Since both conditions are satisfied we can use the normal approximation and the distribution for the proportion is given by:

With the following parameters:

