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In an all boys school, the heights of the student body are normally distributed with a mean of 70 inches and a standard deviation of 3 inches. What is the probability that a randomly selected student will be taller than 71 inches tall, to the nearest thousandth?

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Final answer:

To calculate the probability that a randomly selected student will be taller than 71 inches in an all boys school with a normal distribution of heights and a mean of 70 inches and a standard deviation of 3 inches, we need to convert the height into a z-score and find the area under the standard normal curve to the right of that z-score.

Step-by-step explanation:

Step 1: Define the problem

We have a normally distributed data set with a mean of 70 inches and a standard deviation of 3 inches.

Step 2: Convert the problem to a standard normal distribution

To calculate the probability, we need to convert the height value of 71 inches into a z-score using the formula: z = (x - μ) / σ. Plugging in the values, we get z = (71 - 70) / 3 = 0.3333.

Step 3: Find the probability

To find the probability of selecting a student taller than 71 inches, we need to find the area under the standard normal curve to the right of the z-score.

Using a Z-table or a calculator, we can find that the probability is approximately 0.3693.

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