Mathematics Ratio & Proportion Representational 11–14 yrs

Proportion Graphs

比例图像

Description

Represent proportional relationships using double number lines (two parallel number lines aligned at 0) and ratio tables; recognise that equivalent ratios generate straight lines through the origin when graphed

Mastery Evidence

✓ Plot pairs of proportional values on a coordinate grid and draw the straight line through the origin
✓ Explain why a directly proportional relationship always passes through (0,0)
✓ Read a proportion graph to find an unknown value — e.g. 'If 3 kg costs £6, how much does 5 kg cost?'

Assessment Prompt

If your child is comparing the cost of buying different numbers of cinema tickets, can they sketch a proportion graph — a straight line through zero — and use it to read off the cost of any number of tickets without recalculating each time?