Assignment on unit-1 & 2
1. Modify the data in the base Data worksheet in the Excel file ‘Credit Risk Data’ using IF
function to include new columns, classifying the checking and savings account balances as
low if the balance is less than $250, medium if at least $250 but less than $2000, and high
otherwise.
2. In the ‘Credit Risk Data’ file, apply filter to find the following:
a. All new car loans obtained for single females.
b. All education loans obtained by unskilled workers
c. All used car loans obtained by individuals who are employed 12 months or less.
3. Use database functions to find the average amount of savings for each of the situations
described in problem 2.
4. Use PivotTables to find the number of loans by different purposes, marital status and credit
risk in the Excel file ‘Credit Risk Data’. Illustrate the results in a pivotChart.
5. Based on extensive data from a national high school educational testing program, a standard
deviation of national test scores for mathematics was found to be 118 points and the mean
score is 607. If a sample of 324 students are given the test,
a) What would be the standard error of the mean?
b) What is the probability that a random sample of 324 students will have a
mean score of more than 619?
c) What is the probability that a random sample of 400 students will have a
mean score less than 588?
6. A survey of 50 young professionals found that they spent an average of $20.21 for dining
out, with a standard deviation of $13.88. Find the lower and upper bounds of 95%
confidence interval. Can you conclude statistically that the population mean is greater than
$23?
7. A gym instructor records the weights of a random sample of 31 male high school students.
The mean weight was found to be 140 pounds and the standard deviation of the population
is 20 pounds. How large a sample should be selected to estimate that the mean is within 0.5
with 95% confidence level?
8. According to a magazine people read an average of more than 3 books in a month. A survey
of 20 randon persons found that the mean number of books they read was 2.9 with a
standard deviation of 1.23.
a. To test the magazine’s claim, what should be the appropriate hypotheses be?
b. Compute the test statistic.
c. Using a level of significance of 0.05, what is the critical value?
d. Find the p-value for the test.
e. What is the conclusion?
9. A two-sample test for means was conducted to test whether the mean number of movies
watched each month differed between males and females. The Excel Data Analytics Toll
results are shown below:
t-Test: Two-sample Assuming Unequal variances
Names of Metrics
Mean
Variance
# Observations
Females
5.6
6.267
10
Males
7.5
21.833
10
Hypothesized Mean
0
Difference
df
14
t Stat
-1.133
P(T<=t) one tail
0.138
t Critical one tail
1.76
P(T<=t) two-tail
0.276
t Critical two-tail
2.144
a. Explain how to use this information to draw a conclusion if the null hypothesis is
H0:μF-μM<=0. Clearly state H1, the correct critical value and p-value and your conclusion.
b. Explain how to use this information to draw a conclusion if the null hypothesis is
H0:μF-μM>=0. Clearly state H1, the correct critical value and p-value and your conclusion.
c. Explain how to use this information to draw a conclusion if the null hypothesis is
H0:μF-μM=0. Clearly state H1, the correct critical value and p-value and your conclusion.
10. A manufacturer of automobiles is bringing out a new model. To create its advertising
campaign, the manufacturer wants to determine whether the model’s appear will be
dependent on a particular age group. A sample of a customer survey revealed the following:
Appeal / Age group 
Under 20
20 - 39
40 - 49
50 and above
Like
140
70
70
25
Dislike
60
40
30
65
What can the manufacturer conclude?