/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 56 According to the National Health... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

According to the National Health Center, the heights of 5 -year-old boys are Normally distributed with a mean of 43 inches and a standard deviation of \(1.5\) inches. a. In which percentile is a 5 -year-old boy who is \(46.5\) inches tall? b. If a 5 -year-old boy who is \(46.5\) inches tall grows up to be a man at the same percentile of height, what height will he be? Assume adult men's heights (inches) are distributed as \(N(69,3)\).

Short Answer

Expert verified
a. The 5-year-old boy who is 46.5 inches tall is in the 99th percentile. b. If he grows at the same percentile, he would be 76 inches tall as an adult man.

Step by step solution

01

Finding the Z-score for the boy's height

The Z-score is a measurement of how many standard deviations an element is from the mean. It can be calculated by the formula Z = (X - µ) / σ, where X is the value, µ is the mean and σ is the standard deviation. For the boy who is 46.5 inches tall, the Z-score is (46.5 - 43) / 1.5 = 2.33.
02

Calculating the corresponding percentile for the Z-score

We can find the percentile that corresponds to a Z-score of 2.33 using a standard Normal distribution table or using a percentile calculator. The table gives the area to the left of the Z-score under the standard normal curve, which represents the percentile. In this case, it is about 0.99 or 99%.
03

Predicting the boy's future height

The future height of this 5-year-old boy, assuming he will grow to become a man at the same percentile of height, can be found by using the information about the distribution of adult men's heights: N(69,3). Here, we reverse the Z-score calculation to find the height corresponding to Z=2.33. The formula X = Zσ + µ gives the future height as 2.33*3 + 69 = 76 inches.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

A coin will be flipped four times, and the number of heads recorded. Explain why this is a binomial experiment. Check all four required conditions.

According to the American Veterinary Medical Association, \(36 \%\) of Americans own a dog. a. Find the probability that exactly 4 out of 10 randomly selected Americans own a dog. b. In a random sample of 10 Americans, find the probability that 4 or fewer own a dog.

For each situation, identify the sample size \(n\), the probability of a success \(p\), and the number of success \(x .\) When asked for the probability, state the answer in the form \(b(n, p, x)\). There is no need to give the numerical value of the probability. Assume the conditions for a binomial experiment are satisfied. A 2017 Gallup poll found that \(53 \%\) of college students were very confident that their major will lead to a good job. a. If 20 college students are chosen at random, what's the probability that 12 of them were very confident their major would lead to a good job? b. If 20 college students are chosen at random, what's the probability that 10 of them are not confident that their major would lead to a good job?

A die is rolled 5 times, and the number of spots for each roll is recorded. Explain why this is not a binomial experiment. Name a condition for use of the binomial model that is not met.

A study of U.S. births published on the website Medscape from WebMD reported that the average birth length of babies was \(20.5\) inches and the standard deviation was about \(0.90\) inch. Assume the distribution is approximately Normal. Find the percentage of babies with birth lengths of 22 inches or less.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.