Find the mean for 2, 7, 5, 5, 3, 9, 10, 8, 12, 11.
7.2
9
72
Find the mean for 1, 10, 20, 50, 80, 90, 99.
400
350
50
Find the mean for 47, 48, 49, 50, 51, 52, 53.
300
Find the standard deviation for 100, 121, 123, 145, 151.
4.5
20.5
128
The amounts spent, in \(\pounds\) by a sample of six diners at a restaurant one Saturday evening were: \(\pounds44,\;\pounds47,\;\pounds38,\;\pounds97,\;\pounds40,\;\pounds52\).
Find the standard deviation of amounts spent.
9.9
20.2
22.1
The number of hours of sunshine was recorded daily in Stonehaven over the course of a week.
The results were as follows: 2.4, 3.4, 4.9, 4.0, 3.8, 3.8, 3.6.
Find the standard deviation of the data.
0.3
0.75
0.69
The number of absentees at a school one week were as follows:
32, 29, 33, 33, 38
Calculate the standard deviation for this data.
3.24
2.9
1.62
A random sample of matchboxes is checked.
The total number of matches in the box are: 62, 62, 61, 57, 63.
1.7
2.1
2.35
The pulse rates, in beats per minute, of 6 adults in a hospital waiting area are: 68, 73, 86, 72, 82, 78.
Calculate the standard deviation.
7
6.75
76.5
In 2000 the mean weight of 10 year olds was found to be \(27\,kg\) and the standard deviation was 3.5.
In 2010 the mean weight of 10 year olds was found to be \(29\,kg\) and the standard deviation was 2.1.
Which of these statements is a fair comparison?
In 2000, the weight of 10 year olds was less consistent than in 2010.
In 2010, 10 year olds weighed less on average than in 2000.
In 2010, the weight of 10 year olds was less consistent than in 2000.