What are mode, mean, median and range?

What are mode, mean, median and range?
We explain the meaning of the terms mode, mean, median and range, with examples of how to find each of these from a set of numbers, as well as examples of the types of questions primary-school children might be asked when interpreting data sets.

What is mode, mean, median and range?

Until September 2015, under the old primary curriculum, children in Year 6 studied the mode, mean, median and range. The new curriculum states that they only have to learn about the mean, but they may well learn all the terms anyway.

These mathematical terms can be explained by use of the following results that show the length of time in seconds a group of children took to swim a length:

MarkSusanRitaRebeccaHannahRobertMatthew
91191512910

The mode is the value that appears most often in a set of data. In this case, the mode is 9 seconds.

The mean is the total of all the values, divided by the number of values. To find the mean, we add up all the results and then divide them by the number of swimmers:

9 + 11 + 9 + 15 + 12 + 9 + 10 = 75

75 ÷ 7 = 10.71428.... which can be rounded up to 11

The median is the middle number in a list of numbers ordered from smallest to largest.

9, 9, 9, 10, 11, 12, 15

so 10 is the median of this set of results.

The range is the difference between the lowest value and the highest value, so the range here is 15 - 9 = 6.

Mode, median, medium and range maths problems

In Year 6, children may be given a question like the following:

I asked 12 shoppers on Monday how much money they had in loose change. Here are my results: 35p, 62p, 39p, 99p, 42p, 68p
What is the mean average amount they had? Round your answer to the nearest whole pence.

A child would most likely be allowed a calculator to work out this question.

  • They would need to add up the six amounts which would total 345p and then divide this by six, getting the answer 57.5p.
  • Since the question asks you to round the answer to the nearest whole pence, the final answer would be 58p.

Children may also be asked to analyse results and give a worded answer to a problem, for example:

On Tuesday I asked another group of six shoppers and found they had between 12p and £1.30 each, with a mean value of 56p. What similarities and differences are there between the two groups?

The child would need to say that the range of results is larger, but the mean average is very similar.