To estimate the Mean use the midpoints of the class intervals. Find out how to calculate them and the range of numbers in this KS2 Primary Maths guide. Sum up all the deviations.
Summary For grouped data we cannot find the exact Mean Median and Mode we can only give estimates.
The mode median mean and range are all used to describe a set of numbers. Imagine that we are chopping off the right side of the x-axis. The mean is the average of all the numbers in the set and the range is the difference between the highest and lowest numbers in the set. It also explains how to identify the interval that contains the median an.