Question

The heights of 82 roller coasters have a mean of 285.2 feet and a population standard deviation of 59.3 feet. Find the standardized tests statistics and the corresponding p-value when the claim is that roller coasters are more than 290 feet tall.

Answer 1

0.7673

Explanation:

We have the following:

The null and alternative hypothesis is,

H0: m = 290

Ha: m> 290

x = 285.2

m = 290

sd = 59.3

n = 82

is m the mean, sd the standard deviation and n the population size

Now we calculate the value of z like this:

z = (x - m) / sd / (n ^ (1/2))

z = (285.2 - 290) / 59.3 / (82 ^ (1/2))

z = -0.73

now

P (z> -0.73) = 1 - P (z <-0.73)

we look at the normal distribution table

P = 1 - 0.2327 = 0.7673

Therefore the value of p is equal to 0.7673