Conditional Probability
Q)
At a certain university, 20% of the men and 4% of the women are over 6 feel tall.
Furthermore, 45% of the students are women. If a student is randomly picked and is observed
to be over 6 feet tall, what is the probability that t
Samplesize
Q)
he estimate of the population proportion is to be within plus or minus .05, with a 95 percent level
of confidence. The best estimate of the population proportion is .15. How large a sample is
required? (Round up your answer to the next whole
Standard Devaition
1)
The speeds in miles per hour of the cars passing a certain checkpoint are measured by radar.
The results are shown below.
44.4 41.8 42.9 40.7 43.5
40.1 44.6 41.9 44.4 42.0
43.5 41.9 40.7 43.5 41.8
Find:
Mean _ Range_ Minimum_
Median_
T test for diffrences of means
Q)
Suppose that an automotive parts and accessories chain is experimenting with a new sales
promotion. Two similar stores are selected for the experiment. For Store 1, nothing changes. This
store constitutes the control grou
Test for Single Hypothesis
Q)
1. A forensic psychologist studying the accuracy of a new type of polygraph (lie detector) test
instructed a participant ahead of time to lie about some of the questions asked by the polygraph
operator. On average, the curren
Tets For Single Mean
Q)
An insurance company is reviewing its current policy rates. When originally setting the rates
they believed that the average claim amount was $1,800. Now there are concerns that if the true
mean is actually higher than this they co
T-Test
Q)
A. The speed limit on Division Ave. is 25 miles/hour. Garfield police department (GPD) is
wondering if drivers drive the speed limit.The police department clocks in 26 vehicles and gets
the following results:
22 24 32 28 29 32 26 27 18 28 29 30
t-test for single mean
Q)
A restaurant association says typical household spends a mean of $3306 per year on food away
from home. You are a consumer reporter for a national publication and want to test this claim.
You randomly select 12 households and fin
Z-Score Test
Q)
400 adults are asked whether they favor a bipartisan campaign finance reform bill. If the true
proportion of the electorate in favor of the legislation is 36%, calculate the z-score that fewer
than 50% of those in the sample favor the bill
Z-Test
Q)
Consider the following hypothesis test:
H0:u = 45
Ha:u < 45
A sample of 36 is used. Identify the p-value and state your conclusion for each of the following
sample results. Usea = .01
a. A.) x = 44 and s = 5.2
B.) x = 43 and s = 4.6
c. C.) X = 4
NORMAL DISTRIBUTION
Problem 1:
1. Find the area to the left of 1. First, draw an image, then compute
2. Find the area b/w th right of 2
3. Find the Area between 2 to +2
Problem 2:
1000 students had Written an examination the mean of test is 35 and standar
Z-Test
1. the mean life time of a sample of 500 fluorescent light bulbs produced by a company is
found to be 1, 670 hours with a standard deviation of 150 hours. Test the hypothesis that
the mean life time of bulbs is 1500 hours against the alternative hy
Binomial Distribution :Problem :
A recent national study showed that approximately 55.8% of college students have used
Google as a source in at least one of their term papers. Let X equal the number of students in
a random sample of size n = 42 who have u
Create your own (Student Record) dataset and do the summary statistics
and graphs with interpretation. Use atleast 30 observations with five
variables.
PROBABILITY
Q)
3 marbles are drawn at random from a bag containing 3 red and 5 white marbles.
A. How many different draws are there?
B. How many different draws would contain only red marbles?
C. How many different draws would contain 1 red and 2 white ma
Probability
Q)
There are two coins in a box. One coin is fair, the other has heads on both sides. You reach one
coin at random, toss it, and it lands up heads. What is the probability that it is a two-headed coin?
Statistics and Probability
Ans)
We have 2
Confidence Interval
Q)
Use the given confidencse level and sample data to find a confidence interval for the population standard
deviation O. Assume that a simple random sample has been selected from a population that has a normal
distribution.
Salaries o
Correlation-Coefficeint
Q)
The eruption height and time of interval after eruption of a geyser were measured and are shown below.
Answer parts A-C and please show all your work.
Height (x) 85 135 115 105 95 95 100 125
Interval After (y) 40 62 67 76 69 80
Finding test statistic
Q)
wo different random samples are drawn from 2 different populations. The first sample consists of
20 peoplewith 9 having a common attribute The second consists of 2200 people with 1553
having a common attribute. Compare results fr
Hypothesis Testing
Data provided by the National Association of College Employers indicated that the average
starting salary for graduates with a bachelors Degree in Accounting was $37,000 in 2000. In June
2002 a sample of 48 graduating accounting majors
HYPOTHESIS TESTING
Q)
A recent study examined the drinking behaviors of underage college males and female freshman.
Each participant was asked how many alcoholic beverages they consumed during the past seven
days. The researchers wish to see if there was
MATHS
Q)
A can in the shape of a right circular cylinder is required to have a volume of 500 cubic centimeters. The
top and bottom are made of material that costs 3 cents per square centimeter, while the sides are made of
material that costs 2 cents per s
Mean
Q)
Consider the probability distributions for the random variable x shown here: Find the mean
x 10 20 30 40 50 60
p(x) .05 .20 .30 .25 .10 .10
Find the mean
Ans)
NORMAL DISTRIBUTION-Problems
Q)
assum that adults have iq scores that are normally distributed with the mean of 100 and a
standard deviation 20. a. find the percentage of adults that have an iq between 83 and 117.
b. find the percentage of adults that hav
Normal Distribution
The Gulf stream 100 is an executive jet that seats six, and it has a doorway height of 51.6 in. a)
what percentage of adult men can fit through the door without bending? b) what percentage of
adult women can fit through the door withou
Normal Distribution
A manufacturer produces bearings, but because of variability in the production process, not all of
the bearings have the same diameter. The diameters have a normal distribution with a mean of
1.2 cm and a standard deviation of .01 cm.