Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

Element Hunters. In the article "Element Hunters" (National Geographic, Vol. 233, No. 5, pp. 112-120), R. Dunn reports about the search for new undiscovered elements. Since 1940, scientists have been synthesizing elements one by one. The first was neptunium (Np), element number 93. There are, as of this writing, a total of 26 new synthetic elements. The following table provides their element numbers and symbols.

(a) Suppose that you decide to take a simple random sample of eight of these new elements. Use Table I in Appendix A to obtain eight random numbers that you can use to specify your sample.

(b) If you have access to a random-number generator, use it to solve part (a).

Short Answer

Expert verified

Part (a) Np, Am, Fm, Lr, Ds, FI, Bh, and Rg.

Part (b) Fm, Hs, Cm, Lr, Bh, Es, Fl, and Uus.

Step by step solution

01

Part (a) Step 1. Given information.

The given statement is:

There are a total of 26 new synthetic elements. Firstly we will assign each element a number:

S. No.NumberSymbolS. No.
Number
Symbol
193Np14106Sg
294Pu15107Bh
395Am16108Hs
496Cm17109Mt
597Bk18110Ds
698Cf19111Rg
799Es20112Cn
8100Fm21113Uut
9101Md22114Fl
10102No23115Uup
11103Lr24116Lv
12104Rf25117Uus
13105Db26118Uuo
02

Part (a) Step 2. Obtain a random sample of size 8 by using Table I in Appendix A.

To make an example, use Table I in Appendix A to create an SRS of size 8.

Follow the below-given procedure:

Step 1: Look up random numbers in Table I.

Step 2: Select 10 as the line number.

Step 3: Select Columns 10 and 11.

Step 4: In Line 10-11, begin using two-digit numerals.

Step 5: Pick the first number, which is 01.

Step 6: Avoid digits 27 to 99 and avoid repetition of numerals.

Step 7: Continue up the 12-13 column to get the second number, which is 03.

Step 8: Move up the column to the third number, which is 08

Step 9: Go along the column to the fourth number, which is 11.

Step 10: Go along the column to the fifth number, which is 18.

Step 11: Continue down the column 14-15 until you reach the sixth number, which is 22.

Step 12: Go down the column to the seventh number, which is 15.

Step 13: Count up from 16 to 17 in the column to get the eighth number, which is 19.

Output:

1, 3, 8, 11, 18, 22, 15, 19

The resultant new elements that make up a size 8 SRS are Np, Am, Fm, Lr, Ds, FI, Bh, and Rg.

03

Part (b) Step 1. Use a random number generator to solve part (a).

To get an SRS of size 8 from the population, use MINITAB.


Follow the below-given procedure for MINITAB:

Step 1: Select Calc > Random Data > Integer from the menu bar.

Step 2: Double your selected sample size in the Number of rows of data to generate a section, just in case there are repeats. Set the sample size to eight.

Step 3: In the Store in a column, type SRS in column C1.

Step 4: Enter 01 as the minimum value.

Step 5: Enter 26 as the maximum value.

Step 6: Click the OK button.


MINITAB output is:

13, 16, 4, 11, 15, 7, 22, 25


Therefore, the sample includes Fm, Hs, Cm, Lr, Bh, Es, Fl, and Uus.

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

In each of Exercises 1.55-1.58, fill in the blank (s).

Systematic random sampling is easier to execute than simple random sampling and usually provides comparable results. The exception is the presence of some kind of in the listing of the members of the population.

Working Lottery Winners. In a national poll taken on August 7-11, 2013, by Gallup, Inc., 1039 adults who were employed full or part time were asked the following question: " If you won 10 million dollars in the lottery, would you continue to work, or would you stop working? "Sixty-eight percent of the respondents said that they would continue to work.

(a) Is this study descriptive or inferential? Explain your answer.

(b) The title of the article discussing the survey was " In U.S., Most Would Still Work Even if They Won Millions. " Is the statement in quotes here descriptive or inferential? Explain your answer.

In Exercises 1.92-1.97, we present descriptions of designed experiments. In each case, identify the

(a) experimental units

(b) response variable

(c) factor (s)

(d) levels of each factor:-

(e) treatments.

Highway Signs. A driver's ability to detect highway signs is an important consideration in highway safety. In his dissertation, High way Construction Safety and the Aging Driver, S. Younes investigated the distance at which drivers can first detect highway caution signs. This distance is called the detection distance. Younes analyzed the effect that sign size and sign material have on detection distance. Drivers were randomly assigned to one combination of sign size ( small, medium, and large ), and sign material ( 1, 2, and 3 ). Each driver covered the same stretch of highway at a constant speed during the same time of day, and the detection distance, in feet, was determined for the driver's assigned caution sign.

Number of Farms.The National Agricultural Statistics Service (NASS) conducts studies of the number of acres devoted to farms in each county of the United States. Suppose that we divide the United States into the four census regions (Northeast, North Central, South, and West), take a simple random sample of counties from each of the four regions, and combine all four simple random samples into one sample. What type of sampling design have we used? Explain your answer.

Dental Hygiene: Which Toothbrush? In an experiment reported by J. Singer and D. Andrade in the article " Regression Models for the Analysis of Pretest / Posttest Data " ( Biometrics, Vol . 53, pp . 729-735 ), the effect of using either a conventional or experimental ( hugger ) toothbrush was investigated. Twelve female and 12 male preschoolers were selected. Within each gender group, six were randomly assigned to the conventional toothbrush and the remaining six to the experimental toothbrush. After each subject brushed with the assigned toothbrush, a dental plaque index was measured. The higher the dental plaque index, the greater was the amount of plaque on an individual's teeth.

(a) Is the statistical design described here a completely randomized design or a randomized block design? Explain your answer.

(b) If the statistical design is a randomized block design, what are the blocks?

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