Page 52 - Year 9

Collecting and analysing data Sets 1 and 2 Maths: 1 of 7

Mean Add up the values and divide by how The mean of 3, 4, 7, 6, 0, 4, 6 is Find the mean of:
many values there are.
3 + 4 + 7 + 6 + 0 + 4 + 6 7, 8, 5, 12
= 5
7
Median Value The middle value. Find the median of: Find the median of:

Put the data in order and find the 4, 5, 2, 3, 6, 7,6 a)12, 12, 11, 10, 14
middle one.
Ordered: 2, 3, 4, 5, 6, 6, 7
If there are two middle values, find the Median = 5 b)12, 12, 11, 10, 14, 10
number half way between them by
adding them together and dividing by
2.
Mode / Most frequent/common. Find the mode: Find the mode:
Modal Value There can be more than one mode 4, 5, 2, 3, 6, 4, 7, 8, 4 a) 1, 1, 2
(called bi-modal or multi-modal) or no Mode = 4 Mode:
mode (if all values appear once)
a) 1, 1, 2, 2, 3

Mode:
Range The difference between the highest and Find the range: Find the range:
lowest vales
3, 31, 26, 102, 37, 97
Range is a ‘measure of spread’. The
smaller the range the more consistent a) 1, 2, 3, 4
the data. Range = 102-3 = 99 Range:
Frequency Table A record of how often each value in a 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 7 becomes: 3, 3, 3, 3, 4, 4, 4, 5, 5 becomes
set of data occurs. Mark Tally F
They can be made by using a tally. 3

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