In statistics there are three types of average: the mean, the median and the mode. Measures of spread such as the range and the interquartile range can be used to reach statistical conclusions.
Part of MathsStatistics
The mean is the most commonly used measure of average.
The mean is calculated by adding up all of the data and dividing by the number of items of data.
\(\text{mean} = \frac{\text{sum of all the numbers}}{\text{amount of numbers}}\)
7 babies weigh the following amounts:
2.5 kg, 3.1 kg, 3.4 kg, 3.5 kg, 3.5 kg, 4 kg, 4.1 kg
Find the mean weight of the babies.
\( \text{mean} = \frac{2.5 + 3.1 + 3.4 + 3.5 + 3.5 + 4 + 4.1}{7} = \frac{24.1}{7} = 3.44\) (2 dp)
The mean weight of the babies is 3.44 kg.