A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24 pounds, and the highest is 26 pounds. Each weight is equally likely so the distribution of weights is uniform. A sample of 100 weights is taken.

a) What is the distribution for the sum of the weights of 100 25-pound lifting weights?

b) Find P(Σx < 2,450).

Short Answer

Expert verified
  1. The distribution of the mean weight of the given pounds is;

X~N(2500,57.735/100)

b. The probability PX<2450of is zero.

Step by step solution

01

Given information part(a)

Given in the question that

A manufacturer produces 25-pound lifting weights

The lowest actual weight is 24 pounds

Highest is 26 pounds

02

Solution part(a)

Explanation:

The uniform distribution for lowest 2400pounds and the highest 2600pounds the weight are given as;

localid="1649393005338" X-U(a,b)

XU(2400,2600)

The mean of the uniform distribution is;

μx=a+b2

=2400+26002

=2500

The standard deviation is;

σx=(ba)212

=(26002400)212

=57.735

The mean weight is;

X~NμX,σX/n

03

Given information part(b)

Given in the question that

A manufacturer produces 25-pound lifting weights

The lowest actual weight is 24-pounds

Highest is 26pounds

04

Solution Part (b)

The formula for calculating probability is;

PX<2450

For the calculation we use TI-83 calculator

For this, click on 2nd, then DISTR,

Scroll down to the normalcdf option and enter the provided details.

After this, click on ENTER button of the calculator to have the desired result.

The result shown the calculator is given below.

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 Vaia!

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

Four friends, Janice, Barbara, Kathy and Roberta, decided to carpool together to get to school. Each day the driver would be chosen by randomly selecting one of the four names. They carpool to school for 96days. Use the normal approximation to the binomial to calculate the following probabilities. Round the standard deviation to four decimal places.

a. Find the probability that Janice is the driver at most20days.

b. Find the probability that Roberta is the driver more than 16days.

c. Find the probability that Barbara drives exactly 24 of those 96 days.

Find the probability that the sum of the 40 values is less than 7,000.

Previously, De Anza statistics students estimated that the amount of change daytime statistics students carry is exponentially distributed with a mean of \(0.88. Suppose that we randomly pick 25daytime statistics students.

a. In words,Χ=____________

b.Χ~_____(_____,_____)

c.role="math" localid="1651578876947" Inwords,X=____________

d. X~______(______,______)

e. Find the probability that an individual had between \)0.80and\(1.00. Graph the situation, and shade in the area to be determined.

f. Find the probability that the average of the 25 students was between \)0.80and$1.00. Graph the situation, and shade in the area to be determined.

g. Explain why there is a difference in part e and part f.

Find the probability that the sum of the 40 values is greater than7,500.

Use the following information to answer the next six exercises: Yoonie is a personnel manager in a large corporation. Each month she must review 16 of the employees. From past experience, she has found that the reviews take her approximately four hours each to do with a population standard deviation of 1.2hours. Let Xbe the random variable representing the time it takes her to complete one review. Assume Xis normally distributed. Let Xbe the random variable representing the mean time to complete the 16 reviews. Assume that the 16 reviews represent a random set of reviews.

1. What is the mean, standard deviation, and sample size?

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.

Sign-up for free