GCSE Secondary Maths Age 13-17 - Probability & Statistics: Cumulative Frequency - Explained

The video tutorial explains how to interpret and plot a cumulative frequency graph using a given table of data. It covers the steps to plot points using the upper bound of age intervals and discusses the choice between drawing a smooth curve or a polygon. The tutorial also evaluates a claim about the percentage of workers older than 65 using the graph, demonstrating how to calculate percentages and verify claims. The importance of reading questions carefully and understanding the marking criteria is emphasized.

What does a cumulative frequency table provide information about?

• The cumulative total of items up to each category

• The number of items in each category

• The total number of items

• The average number of items per category

When plotting a cumulative frequency graph, which point should be used?

• The lower bound of each interval

• The midpoint of each interval

• The upper bound of each interval

• The average of the interval

What are the two options for joining points on a cumulative frequency graph?

• Using a dashed line or a solid line

• Using a bar graph or a line graph

• Drawing a curve or a polygon

• Connecting with arrows or dots

What is the cumulative frequency value for the upper bound of 50 years?

• 200

• 186

• 175

• 194

How many marks are allocated for correctly plotting points and joining them?

• 2 marks

• 1 mark

• 3 marks

• 4 marks

What percentage of workers are older than 65 according to the graph?

• 10%

• 15%

• 20%

• 5%

What is the correct conclusion about Graham's statement regarding workers older than 65?

• Graham's statement cannot be determined

• Graham's statement is partially correct

• Graham is incorrect

• Graham is correct