A grouped data frequency table is shown.
What is the mean for this set of data?
- 6.5
- 10.5
- 11.9
- 12.4
Statistics, STD2 S1 2006 HSC 23c
Vicki wants to investigate the number of hours spent on homework by students at her high school.
- Briefly describe a valid method of randomly selecting 200 students for a sample. (1 mark)
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- Vicki chooses her sample and asks each student how many hours (to the nearest hour) they usually spend on homework during one week.
The responses are shown in the frequency table.
What is the mean amount of time spent on homework? (2 marks)
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Show Worked Solution
i.
MARKER’S COMMENT: This “routine” exercise of finding a mean from grouped data was incorrectly answered by most students! The best responses copied the table and inserted a class-centre column (see solution).
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Statistics, STD2 S1 2014 HSC 14 MC
Twenty Year 12 students were surveyed. These students were asked how many hours of sport they play per week, to the nearest hour.
The results are shown in the frequency table.
What is the mean number of hours of sport played by the students per week?
- 3.3
- 4.3
- 5.0
- 5.3