Basic Business Statistics Assignment Report

Basic Business Statistics:
Student Name:
Instructor Name:
Course Number:
17th April 2020

PART A – Multiple Choice (1 mark per question) Please circle
your answer on the test paper
1) Suppose that you wish to test a claim about a population mean. Which
distribution should be used given that the sample is a simple random sample, σ
is not known, n = 40 and the population is normally distributed?
a. The z-distribution
b. The t-distribution
c. The Chi-Square Distribution
d. The F-distribution
Answer
A: The z-distribution
2) A hypothesis in statistics is a claim or a statement about a
a. population parameter
b. legitimate inheritance
c. weather conditions
d. sample statistic
Answer
A: Population parameter
3) A market researcher selects 100 people as they left Square one Mall. What
method is being used to select the sample?
a. cluster sampling
b. stratified random sampling
c. Simple Random sampling
d. systematic sampling
Answer
C: Simple random sampling
4) Type I error is
a. the mistake of rejecting the null hypothesis when it is false.
b. the mistake of failing to reject the null hypothesis when it is false.
c.the mistake of rejecting the null hypothesis when it is true.
d. the mistake of failing to reject the null hypothesis when it is true.
Answer

C: The mistake of rejecting the null hypothesis when it is true
5) Which of the following values could represent a correlation coefficient?
a. -1.045
b. 1.05
c. 1.928
d. – 1
Answer
D: -1
6) Which of the following would be an appropriate null hypothesis?
a. The mean of a population is equal to 100
b. The mean of a sample is equal to 100.
c. The mean of a population is greater than 100.
d. The mean of a sample is less than 100.
Answer
A: The mean of a population is equal to 100
7) The width of a confidence interval estimate of the population mean decreases
when the:
a. level of confidence increases.
b. sample size decreases.
c. value of the population standard deviation decreases.
d. all of these choices are true.
Answer
C: Value of the population standard deviation decreases
8) Assume n1 = 382 and x1 = 72, n2 = 183 and x2 = 69, calculate the pooled
sample proportion p.
a. 0.125
b. 0.175
c. 0.225
d. 0.250
Answer
D: 0.250
9) The effectiveness of a headache medicine is tested by measuring the intensity of
a headache in patients before and after drug treatment. The data consists of

before and after measurements for each patient. Determine whether the
samples are independent or dependent or neither.
a. Independent
b. Dependent
c. Neither
d. Not enough information
Answer
B: Dependent
10) In a perfectly symmetric bell shaped "normal" distribution:
a. The mean equals the median.
b. The mean equals the mode.
c. The median equals the mode.
d. All of these choices are true.
Answer
D: All of these choices are true
PART B – Problem Section COMPLETE
ALL QUESTIONS
Question 1 (8 marks)
At a major credit card company, the percentages of people who historically apply
for Silver, Gold and Platinum cards are 55%, 35% and 10% respectively. In a recent
sample of customers responding to a promotion, of 200 customers, 100 applied for
silver, 60 for Gold and 40 for Platinum. At 10% level of significance is there
evidence to suggest that the percentages for this promotion may be different from
the historical proportions? Use χ2
distribution
Type of Card Observed
Frequency
O
Expected
Frequency E =
np
O – E (O – E)2 ( O−E ) 2
E
Silver 100 110 -10 100 0.90909091
Gold 60 70 -10 100 1.42857143