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A theme park's rides are rated as mild, moderate and

max. They have restrictions requiring that passengers
have heights of at least 42 inches, 48 inches, and 54
inches, respectively. Suppose the population of children
attending the park has a mean height of 53 inches with
a standard deviation of 4 inches.
If a child is chosen randomly, what is the probability
that: (Round all answers to nearest thousandths)
a) the child can go on all rides?
b) the child can participate in only mild and moderate
rides?
c) the child can only go on mild rides?
d) the child is excluded from all rides?

User Jjmaestro
by
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1 Answer

4 votes

Answer:

the probability that a child is excluded from all rides is 0.5000 (rounded to three decimal places).

Explanation:

We can use the standard normal distribution to solve this problem. We first need to standardize the height requirements using the population mean and standard deviation.

a) To find the probability that a child can go on all rides, we need to find the probability of getting a height of at least 54 inches.

z-score = (54 - 53) / 4 = 0.25

Using a standard normal table or calculator, we find that the probability of getting a z-score of 0.25 or greater is 0.4013.

Therefore, the probability that a child can go on all rides is 0.4013 (rounded to three decimal places).

b) To find the probability that a child can participate in only mild and moderate rides, we need to find the probability of getting a height between 42 inches and 48 inches.

First, we find the z-scores for each height requirement:

z-score for 42 inches = (42 - 53) / 4 = -2.75

z-score for 48 inches = (48 - 53) / 4 = -1.25

Using a standard normal table or calculator, we find that the probability of getting a z-score between -2.75 and -1.25 is 0.2375.

Therefore, the probability that a child can participate in only mild and moderate rides is 0.2375 (rounded to three decimal places).

c) To find the probability that a child can only go on mild rides, we need to find the probability of getting a height of less than 42 inches.

z-score = (42 - 53) / 4 = -2.75

Using a standard normal table or calculator, we find that the probability of getting a z-score of -2.75 or less is 0.0030.

Therefore, the probability that a child can only go on mild rides is 0.0030 (rounded to three decimal places).

d) To find the probability that a child is excluded from all rides, we need to find the probability of getting a height less than 42 inches or greater than 54 inches.

First, we find the z-scores for each height requirement:

z-score for 42 inches = (42 - 53) / 4 = -2.75

z-score for 54 inches = (54 - 53) / 4 = 0.25

Using a standard normal table or calculator, we find that the probability of getting a z-score of less than -2.75 or greater than 0.25 is 0.0987 + 0.4013 = 0.5000.

Therefore, the probability that a child is excluded from all rides is 0.5000 (rounded to three decimal places).

User Charming
by
7.7k points