Mathematics
Statistics
Class 7
Intermediate
About 20 min
Premium
Mean, median and mode: a vegetable stall's sales
Drag the stacks of tomato crates sold each day and watch the mean, median, mode and range change.
Core concept
The mean shares the total out equally, the median is the middle value, and one unusual value moves the mean far more than the median
Topic: Statistics
A vegetable stall at the haat bazaar keeps count of the crates of tomatoes it sells each day. Three numbers sum up the days. The mean is the total shared out equally: total ÷ number of days. The median is the middle day when the days are put in order. The mode is the value that comes up most often. The range, most − least, shows how spread out the days are. One very busy day, such as a festival, can change these numbers in very different ways.
What you will learn
- Find the mean, median, mode and range of a small set of data.
- Read and change a bar graph.
- Explain why an unusual value moves the mean more than the median.
Before you start
- Add whole numbers and divide by a small number.
Materials
- A notebook of daily sales
Equipment
- Squared paper for a bar graph
Procedure
- Drag a stack of crates up or down to change how many were sold that day.
- Watch the orange mean line, the purple median line, the sorted row, the mode and the range.
- Make every day sell the same, and record it.
- Add one very busy festival day, then make the mean exactly 6 and exactly 5 in other ways, and record each.
How this simulation is simplified
- Only whole crates are sold.