Edexcel IGCSE Maths topic guide

Statistics and Data Handling

Statistics questions test both calculation and interpretation. A correct value may not earn every mark unless it is connected to the context, the sampling method or the limitations of the data.

Foundation and Higher relevance

Foundation and Higher cover averages and common charts. Higher work includes frequency density, cumulative frequency, interpolation and more detailed comparison of distributions.

Topic coverage

Mean, median and mode
Range and interquartile range
Grouped frequency tables
Bar charts and pie charts
Time series
Scatter graphs and correlation
Histograms and frequency density
Cumulative frequency and box plots

Worked example

Question: A histogram class from 20 to 30 has frequency 18. Find its frequency density.

Calculate the class width: 30 − 20 = 10.
Use frequency density = frequency ÷ class width.
Calculate 18 ÷ 10.

Answer: The frequency density is 1.8.

Common errors

Using bar height as frequency when histogram class widths differ.
Calculating a mean from grouped data without using class midpoints.
Describing correlation as proof that one variable causes another.

Revision checklist

I distinguish frequency from frequency density.
I can compare distributions using a measure of centre and spread.
I write interpretations in the context of the data.