MAT 121 Study Guide - Midterm Guide: Simple Random Sample
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MAT 121 Final Exam December 10,2008 Version 1 Page 1
There are 10 questions. Do all parts of all questions. Show the work you do
to obtain an answer. A calculator and your textbook are allowed. No other books
or notes are allowed. Make sure you have seen and understand the material in
the syllabus about what sort of notes you are allowed to put in your book. Do not
share calculators.
Put your name on your blue book. Put all the work you wish to have graded
in your blue book. Turn in both your exam and your blue book together. When
you turn in your exam make sure your name gets checked off the list as having
turned in the exam.
1. (6 points) ln each case tell whether the information given is at the nominal,
ordinal, interval, or ratio level of measurement. The number or word in
parentheses indicates what data you are to classify.
(a) That house is yellow. (yellow)
(b) Ihat house cost $120,000. ($120,000)
2. (6 points) ln each case tell whether the sample is being selected by random,
systematic, cluster, stratified, or convenience sampling.
(a) A college wishes to conduct a survey of its freshman class. lt puts the
names of all the freshmen in alphabetical order, then picks every 20th name and
interviews them.
(b) To conduct a phone survey a marketing firm has a computer randomly
generate phone numbers then dials those numbers and talks to whoever
answers.
3. (B points) lVlake a stem-and-leaf plot of the following data. Use the integer part
of each number as the stem.
4.8 3.3 5.9 2.1 4.2 3.7 5.4 2.0 4.6 3.5
4. (10 points) ln a box of 200 computer chips 30 of them are defective. lf 3 chips
are chosen at random with replacement, what is the probability that at least one
of them is defective?
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Document Summary
Mat 121 final exam december 10,2008 version 1 page 1. Show the work you do to obtain an answer. Make sure you have seen and understand the material in the syllabus about what sort of notes you are allowed to put in your book. Put all the work you wish to have graded in your blue book. Turn in both your exam and your blue book together. Use the integer part of each number as the stem. I 11 14 15 17 19 21 24 27: (12 points) for the following list of numbers compute the mean, median, and sample standard deviation. I 13 15 19: (1 2 points) weights of pumpkins f rom a certain f ield have a mean of 17 "2 pounds and a standard deviation of 4,2 pounds. A simple random sample of 55 pumpkins is taken from that field.
