Math 161B
Quiz 7
Solution
29 March 2017
1. The heights of the men in this years senior class at Wild West College are normally
distributed with a mean of 72.0 inches and a standard deviation of 3.2 inches.
What percentage of men in this years WWC senior c
Math 161E
Quiz 8
Solution
9 April 2014
1. The children at Slippery Hills Day Camp have weights that are normally distributed
with a mean of 100 pounds and a standard deviation of 14 pounds. Find the probability,
if a random sample of nine of these childre
Math 161B
Quiz 8
Solution
9 April 2014
1. The children at Slippery Hills Day Camp have weights that are normally distributed
with a mean of 100 pounds and a standard deviation of 13 pounds. Find the probability,
if a random sample of nine of these childre
Math 161 B
Hour Exam II Solutions
23 April 2014
Part 1: Multiple choice. Circle your answer.
1. A company manufactures batteries in batches of 18 and there is a 3% rate of defects
(i.e., the probability that a battery is defective is 0.03). Find the proba
Math 161E
Quiz 6
Solution
26 March 2014
1. To play the Five-Ten Lottery, you pay an entry fee of $1 and select ve numbers from
the set cfw_1, 2, 3, . . . , 10. The Lottery Commission then selects ve winning numbers
from the same set. If the winning number
Math 161E
Quiz 7
Solution
2 April 2014
1. Find the z-score that separates the highest 19% of the values of a standard normal
random variable from the rest.
Solution: We want the area to the left of z =
to be (100 19)% = 82%, or 0.8100.
Area = 0.8100
0
0.8
Math 161 E
Hour Exam II Solutions
23 April 2014
Part 1: Multiple choice. Circle your answer.
1. A company manufactures batteries in batches of 18 and there is a 3% rate of defects
(i.e., the probability that a battery is defective is 0.03). Find the proba
Math 161E
Quiz 9
Solution
16 April 2014
The weights of the oranges at Orrins Orange Grove are normally distributed. In a sample
of 23 oranges, the mean weight was 10.5 ounces and the (sample) standard deviation was
1.3 ounces.
1. Construct a 99% condence
Essay Answers from the Spring 2013 Math 161 Final Exam
Note: These are abbreviated answers to the essay questions, for review purposes only. To
earn full credit for an essay answer on the nal exam, you will need to show all your work.
2
1. The sample mean
Spring 2102 essay answers
1. TS: 2 5.612. The critical 2 value is 4.605. We reject independence. At the
= 0.10 signicance level, the sample data support the claim that the two variables
are dependent.
2. The margin of error is about 5.17%. We are 95% con
Math 161B
Quiz 9
Solution
16 April 2014
The weights of the oranges at Orrins Orange Grove are normally distributed. In a sample
of 23 oranges, the mean weight was 10.5 ounces and the (sample) standard deviation was
1.3 ounces.
1. Construct a 90% condence
Multiple-Choice Answers from the Spring 2013 Math 161 Final Exam
1. (c) The median is 3.8, and the range is 5.2 2.3, which is 2.9.
2. (a) If X is binomial with p = 0.55 and n = 4, then P (X = 3) + P (X = 4) is about
0.39098.
3. (e) The 97th percentile for