Suppose the test scores on a final exam are normally distributed with a mean of 74 and a standard deviation of 3. What is the probability that a randomly selected test has a score higher than 77?

We have been given that the test scores on a final exam are normally distributed with a mean of 74 and a standard deviation of 3. We are asked to find the probability that a randomly selected test has a score higher than 77.

First of all, we will find z-score corresponding to sample score 77.

, where,        

z = z-score,

x = Random sample score,

= Mean,

= Standard deviation.

Now we need to find .

We will use formula to find the probability greater than a z-score of 1.

Using normal distribution table, we will get:

Therefore, the probability that a randomly selected test has a score higher than 77 would be 0.15866.

c

-by-step explanation:

it would be c