Compute xbar, s2, and sfor each of the following data sets. If appropriate, specify the units in which your answer is expressed.

a.3, 1, 10, 10, 4

b.8 feet, 10 feet, 32 feet, 5 feet

c.-1, -4, -3, 1, -4, -4

d.1/5 ounce, 1/5 ounce, 1/5 ounce, 2/5 ounce, 1/5 ounce, 4/5 ounce

Short Answer

Expert verified
  1. Xbar = 5.6, s2 = 17.3, s = 4.159
  2. Xbar = 13.75 feet, s2 = 152.25, s = 12.338 feet
  3. Xbar = -2.5, s2 = 4.35, s = 2.085
  4. Xbar = 0.33 ounce, s2 = 0.05868, s = 0.242 ounce

Step by step solution

01

 Step 1: Finding  ,s2, s

x = 3, 1, 10, 10, 4
x¯=xn=3+1+10+10+45=285=5.6

x

(xx¯)

(xx¯)2

3

3 – 5.6 = -2.6

6.76

1

1 – 5.6 = -4.6

21.16

10

10 – 5.6 = 4.4

19.36

10

10 – 5.6 = 4.4

19.36

4

4 – 5.6 = -1.6

2.56

Sum

0

69.2


s2=(χχ-)2n1=69.251=69.24=17.3

s=s2=17.3=4.159

Therefore, localid="1651308857080" x¯= 5.6, s2 = 17.3, s = 4.159

02

Calculating  x¯,s2, s

x = 8 feet, 10 feet, 32 feet, 5 feet

χ-=χn=8+10+32+54=554=13.75

s2=(χχ-)2n1=456.7541=456.753=152.25

s=s2=152.25=12.338

Therefore,x¯ = 13.75 feet, s2 = 152.25, s = 12.338 feet

03

Computing x¯ ,s2, s

x = -1, -4, -3, 1, -4, -4

χ-=χn=(1)+(4)+(3)+1+(4)+(4)6=156=2.5

s2=(χχ-)2n1=21.7561=21.755=4.35

s=s2=4.35=2.085

Therefore, x¯= -2.5, s2 = 4.35, s = 2.085

04

Finding x¯  ,s2, s

x = 1/5 (0.2) ounce, 1/5 (0.2) ounce, 1/5 (0.2) ounce, 2/5 (0.4) ounce, 1/5 (0.2) ounce, 4/5 (0.8) ounce

χ-=χn=0.2+0.2+0.2+0.4+0.2+0.86=26=0.33

s2=(χχ-)2n1=0.293461=0.29345=0.05868

s=s2=0.05868=0.242

Therefore, x¯= 0.33 ounce, s2 = 0.05868, s = 0.242 ounce.

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

Permeability of sandstone during weathering.Refer to the Geographical Analysis(Vol. 42, 2010) study of the decay properties of sandstone when exposed to the weather, Exercises 2.47 and 2.65 (pp. 96 and 104). Recall that slices of sandstone blocks were measured for permeability under three conditions: no exposure to any type of weathering (A), repeatedly sprayed with a 10% salt solution (B), and soaked in a 10% salt solution and dried (C).

a.Combine the mean (from Exercise 2.47) and standard deviation (from Exercise 2.65) to make a statement about where most of the permeability measurements for Group A sandstone slices will fall. Which rule did you use to make this inference and why?

b.Repeat part afor Group B sandstone slices.

c.Repeat part afor Group C sandstone slices.

d.Based on all your analyses, which type of weathering (type A, B, or C) appears to result in faster decay (i.e., higher permeability measurements)?

Calculate the mode, mean, and median of the following data:

18 10 15 13 17 15 12 15 18 16 11

Salary offers to MBAs.Consider the top salary offer (in thousands of dollars) received by each member of a sample of 50 MBA students who graduated from the Graduate School of Management at Rutgers, the state university of New Jersey. Descriptive statistics and a box plot for the data are shown on the XLSTAT printouts at the top of the next column. [Note:The “+” on the box plot represents the location of the mean.]

a.Find and interpret the z-score associated with the highest salary offer, the lowest salary offer, and the mean salary offer. Would you consider the highest offer to be unusually high? Why or why not?

b.Based on the box plot for this data set, which salary offers (if any) are suspect or highly suspect outliers?

Using only integers between 0 and 10, construct two data sets with at least 10 observations each so that the two sets have the same mean but different variances. Construct dot plots for each of your data sets and mark the mean of each data set on its dot diagram.

Question: In business, do nice guys really finish last?Do “nice guys finish last” in the competitive corporate world? In a study published in Nature(March 20, 2008), college students repeatedly played a version of the game “prisoner’s dilemma,” where competitors choose cooperation, defection, or costly punishment. (Cooperation meant paying 1 unit for the opponent to receive 2 units; defection meant gaining 1 unit at a cost of 1 unit for the opponent, and punishment meant paying 1 unit for the opponent to lose 4 units.) At the conclusion of the games, the researchers recorded the average payoff and the number of times punishment was used against each player. A graph of the data

is shown in the accompanying scatterplot. Does it appear that average payoff is associated with punishment use? The researchers concluded that “winners don’t punish.” Do you agree? Explain.

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