STAT177 homework sheet #1
These are age statistics from the Outreach department at Calgary Urban Project Society.
|
Class |
Frequency |
Relative frequency |
Cumulative relative frequency |
|
< 13 |
2 |
0.0007 |
0.0007 |
|
13-20 |
91 |
0.0332 |
0.0340 |
|
20-30 |
744 |
0.2716 |
0.3056 |
|
30-40 |
1087 |
0.3969 |
0.7024 |
|
40-50 |
577 |
0.2107 |
0.9131 |
|
50-60 |
164 |
0.0599 |
0.9730 |
|
60+ |
74 |
0.0270 |
1 |
1) What percentage of the clients are under 40? (70.24%)
2) What percentage of the clients are at least 20? (96.60%)
3) What percentage of the clients are at least 20 but under 40? (66.85%)
4) In which class would you find the median? (30-40)
5) Create a histogram of the data using a frequency scale. Which way does the data appear to be skewed? (data appears symmetric)
A survey of 20 Calgarians was taken to determine the number of times per month they ate out. These were the results:
|
4 |
6 |
1 |
4 |
|
5 |
1 |
7 |
8 |
|
2 |
3 |
4 |
5 |
|
3 |
2 |
3 |
4 |
|
6 |
4 |
2 |
3 |
6) Is this data continuous or discrete? (discrete)
7) Create a frequency table of the data using a class width of 2. (first class = 1-2; second class = 3-4 etc.)
8) What percentage eat out no more than 6 times per month? (90%)
9) What percentage eat out more than twice per month? (75%)
10) What is the mean and standard deviation? (3.85 and 1.9)
11) Does the data contain any outliers? (no outliers)
The percentage of people who do their own income tax return is 87%. The percentage of people who get a refund is 76%. The percentage of people who file their own return and get a refund is 68%.
12) What percentage of people either do their own return or get a refund? (95%)
13) What percentage of people who do their own return get a refund? (78.16%)
14) Are those who do not do their own return more likely to get a refund than those who do? (61.54% of those who do not do their own return get a refund. The answer is no.)
A credit card company conducted a survey with 10,000 people to determine if there is a link between annual household income and credit card balances. These were the results:
|
Balance|Income |
<$35K |
$35K -
$50K |
$50K -
$75K |
$75K -
$100K |
$100K+ |
Total |
|
<
$500 |
0.0106 |
0.0508 |
0.0192 |
0 |
0 |
0.0806 |
|
$500 -
$1000 |
0.0169 |
0.1377 |
0.0826 |
0.0254 |
0.0064 |
0.269 |
|
$1000
- $5000 |
0 |
0.089 |
0.1419 |
0.0911 |
0.0254 |
0.3474 |
|
$5000+ |
0 |
0.0254 |
0.0805 |
0.1229 |
0.0742 |
0.303 |
|
Total |
0.0275 |
0.3029 |
0.3242 |
0.2394 |
0.106 |
1 |
15) What percentage has a credit card balance under $1000? (34.96%)
16) What percentage of those who earn between $35,000 and $50,000 has a credit card balance under $1000? (62.23%)
17) What percentage of those who earn less than $75,000 has a credit card balance under $1,000? (48.55%)
18) What percentage of those who have a credit card balance of at least $1000 has an annual household income of at least $50,000 (82.41%)
19) If a household has a balance card balance of at least $1000, which income bracket are they most likely to belong to? ($50K - $75K at 34.19%)
20) Phrase which income/balance categories are mutually exclusive in a way that would go in a report. (No-one with income of $75,000 or more has a balance under $500. No-one with income under $35,000 has a balance of $1000 or more)
From the text, read:
Chapter 1 pages 13-23
Chapter 2 pages 24-28
You will note that the text has some material that we do not cover in class. For tests and assignments, you need to learn only that which is covered in class. However, if you would like to learn material from the text that we do not cover in class, I’d be happy to show you.