Maths Quest A Year 11 for QueenslandChapter 10 Describing, exploring and comparing data WorkSHEET 10.21
WorkSHEET 10.2Describing, exploring and comparing data
Name: ______
Maths Quest A Year 11 for QueenslandChapter 10 Describing, exploring and comparing data WorkSHEET 10.21
1 / The following data show the survey results of the number of children in families.Data:
3, 5, 2, 4, 3, 1, 4, 1, 2, 5, 3, 6, 4, 3, 5, 4, 4.Create a frequency table for this data. /
2 / Using the frequency table from question 1 find:
(a)the mean number of children per family
(b)the median number of children per family
(c)the modal number of children per family / (a)
(b)1, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 6,
Median = 4
(c)Mode = 4
3 / Lachlan has calculated his mean mathematics score to be 67%, based on eight tests. If he scores 75% on the ninth test, what will his new mean score be? /
Lachlan’s new mean score will be 68%.
4 / A shoe company surveyed the shoe size purchased by women over a period of time.
The results were as follows:
8, 5, 6, 5, 8, 6, 7, 9, 5, 7, 6, 8, 8, 6, 9, 7, and 8.
(a)Calculate the mean of this data
(b)Find the modal value.
(c)Find the median value.
(d)Which of these values would be of the most use to the company? Why? / (a)
The mean shoe size is 7.
(b)The mode is 8
(c)5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 8, 9, 9,
The median value is 7.
(d)The mode would probably be of the most value because this is the shoe size that they sell the most.
5 / Tom has been earning some extra pocket money by washing cars.
In each hour block he has managed to wash 4 cars, 5 cars, 3 cars, 4 cars and 4 cars.
The mean number of cars that he has been able to wash is therefore 4 cars per hour.
In order to increase his mean to 5 cars per hour, how many cars does Tom need to wash in the next hour? Is this likely? /
Tom needs to wash 10 cars in his next hour.
No, this is not very likely.
6 / This grouped frequency table gives the number of ‘salmon cod’ caught by a fisherman on 25 fishing trips.
Add a cumulative frequency column to the table, then use this to determine the median class. /
/ 4
7 / Use the frequency distribution table in questions 6 to calculate the mean number of ‘salmon cod’ caught by the fisherman on his 25 fishing trips. /
8 / From the distribution table in question 6, determine the modal class. / modal class = 45 – 49 cod.
9 / The number of goals scored by a team is shown below:
5, 4, 4, 7, 5, 9, 12, 14, 16, 16.
(a)Find the lower quartile.
(b)Find the upper quartile.
(c)Find the interquartile range. / 4, 4, 5, 5, 7, 9, 12, 14, 16, 16
LQ median UQ
(a)Lower quartile = 5
(b)Upper quartile = 14
(c)Interquartile range= 14 5
= 9 / 2
10 / Use your calculator to find the standard deviation of the set of outcomes when a
six-sided die is rolled as shown below.
1, 2, 3, 4, 5, 6
State your answer correct to two decimal places. / Standard deviation = 1.87 / 1