Page 101 - Knowledge Organiser Yr7 24-25
P. 101
By the end of this topic you should be able to:
• Write a proportion as a fraction or a percentage
• Increase or decrease 2 quantities using direct proportion
• Solve problems using direct proportion
• The unitary method of proportion
• Simplify a ratio
• Understand and use the relationship between ratio and proportion
Language
Meaning
Example
Proportion
Compares a part to the whole and can be written as a fraction
Ratio
Compares 2 or more parts. You write a ratio using a colon :
Direct Proportion
Two quantities that increase or decrease by the same proportion
Unitary method
The method of dividing into a given ratio or proportion using the value of one equal share
150g of cereal is £2.25
1g is £0.015 (divide by 150) 700g is £10.50
(multiply by 700)
Important things to remember:
1) Ratio compares the size of the parts
2) Proportion compares the size of a part with the whole
Worked examples
101
Knowledge Base: Mathematics TOPIC 10: Proportionality Year 7 | Summer Term 1