Really Basic A level Statistics Test. (Multiple Choice)

1) ‘Cluster sampling’ is a term given to one method of
(a) Selecting random numbers using excel
(b) Probabilistic sample selection
(c) Snowballing
(d) Downloading secondary data
(e) Selecting a population

2) ‘Stratified sampling’ may provide greater precision of population estimates, compared to ‘simple random sampling’ because it
(a) only applies to collecting secondary data
(b) requires the whole population to be sampled
(c) makes use of supplementary information
(d) always divides the population into geographic areas
(e) all of the above

Data for questions 5, 6 and 7
The data below describes the test marks from a class of fifteen students. They represent the marks from the full group, ie the total population. Use this data for questions 5 and 6 and 7.
Marks: 38, 60, 63, 45, 47, 45, 72, 75, 31, 51, 72, 66, 62, 54, 59.

5) Are the population mean and the median (to 2dp):
(a) 56 and 56.5
(b) 56 and 59
(c) 58 and 59.5
(d) 58 and 60
(e) None of the above
6) Are the range and the average deviation (to 2dp):
(a) 44 and 0
(b) 44 and 10.8
(c) 37 and 0
(d) 75 and 10.8
(e) None of the above

7) Are the standard deviation and coefficient of variation from this population (to 2 dp):
(a) 12.61 and 0.23
(b) 12.61 and 4.44
(c) 13.05 and 0.23
(d) 13.05 and 4.29
(e) None of the above

8) A population was found to have a standard deviation of 3, a mean of 14, a mode of 8, and a median of 10. Is the frequency distribution:
(a) Positively skewed
(b) Negatively skewed
(c) A completely symmetrical distribution
(d) Bimodal
(e) Cannot be described without further information

Use the data below for questions 9, 10, 11 and 12. The data describes the ages of the whole population on a mailing list. It is being evaluated by a company that is considering buying the list.

The ages (in years) of the 50 individuals on the mailing list, in ascending order are:
These 50 ages average 35.

9) Is the variance of this raw data (to two decimal places):
(a) 14.86
(b) 216.4
(c) 220.522
(d) 10820.0
(e) none of the above

Put the raw data into class intervals of:
Class Mid Point (xi)
0 -< 16 12
16 -< 21 18.5
21 -< 30 25.5
30 -< 40 35
40 -< 60 50
> 60 65

10) Is the mean of the grouped data (to 2 dp):
(a) 8.63
(b) 35.0
(c) 35.54
(d) 206.0
(e) None of the above

11) You wish to consider the accuracy of your estimate in the previous
question. The percentage error for the estimate of the mean of the
grouped data is (to 2 dp):
(a) – 0.54%
(b) – 0.2
(c) 0%
(d) + 0.02%
(e) None of the above

12) Is the median of the grouped data (to2 dp):
(a) 32.17
(b) 35.32
(c) 35.91
(d) 45.91
(e) None of the above

13) When calculating the median from grouped data which of the
following is assumed:
(a) All observations are integers
(b) All observations are spread evenly throughout their class
(c) All classes are of the same width
(d) All classes are of different widths
(e) All observations are located at the class mid point

14) For a standard normal (Z) variable ie. Z~N(0,12), p(1.6<Z<1.8) is (to accuracy of 4dp):

(a) 0.0189
(b) 0.4811
(c) 0.5189
(d) 0.9093
(e) None of the above

15) For a standard normal (Z) variable ie. Z~N(0,12), p(Z > -2.22) is (to accuracy of 4dp):
(a) 0.0132
(b) 0.4861
(c) 0.4868
(d) 0.9861
(e) 0.9868


Ambassador to the humans
Hi! :welcome: We are glad that you posted here! This looks like a homework question though. Our homework help policy can be found here. We mainly just want to see what you have tried so far and that you have put some effort into the problem. I would also suggest checking out this thread for some guidelines on smart posting behavior that can help you get answers that are better much more quickly.
1B 2C 5B 6B 7C 8A 9C 10C 11A 12E 13C 14 A 15 A

This is due tomorrow. i would really appreciate if you could check my answers.
this counts as 10% of my final mark!
its a multiple choice question. they don't need my reasoning. but u want me to spent my time typing it here?
i thought this was a forum that would help me. not ppl that judge me and i have to prove my self first to get advice.
ill say it again that this is for tomorrow morning. i dnt have the time to satisfy you.
im really disappointed and sad with your replies and the way u talk to me.


Super Moderator
If you aren't willing to take the time to read and follow our homework policy, do you think it's really fair to demand us to take time out of our days to help you?


This is what I got:

1H 2C 5W 6B 7R 8A 9C 10B 11A 12E 13L 14 A 15 T

But I didn't use any reasoning because it's multiple choice.

Alice15492 we really want to help people understand stats better. We love stats and want other people to be passionate too. When you post an entire assignment and ask us to check it it really cheapens what we do. Many of us are actually professionals some even profs and providing you with a straight up check of your HW would be at best unethical. Certain questions or concepts? Sure we're here for that but checking answers to an assignment really isn't what we do.

Are there particular problem's you're struggling with? Concepts?