Understanding Ratios and Proportional Relationships
Ratios are fundamental mathematical concepts used to compare quantities and establish relationships between numbers. When working with ratios, it's essential to understand how to simplify them to their most basic form, making calculations more manageable and clearer to understand.
Definition: A ratio is a mathematical comparison between two or more related quantities, expressed as "a:b" or "a:b:c" for three quantities.
When simplifying ratios, we divide all parts by their greatest common factor. For example, in the ratio 15:25:10, we can divide all numbers by 5 to get the simplified ratio 3:5:2. This maintains the same proportional relationship while using smaller numbers.
Working with real-world applications of ratios involves dividing quantities into given proportions. For instance, when sharing £300 between three people in the ratio 3:4:5, first add the ratio parts to determine that £300 represents 12 equal parts. Then calculate the value of one part and multiply by each person's ratio number to find their share: £75, £100, and £125 respectively.
Example: To divide £300 in the ratio 3:4:5:
- Calculate total parts: 3 + 4 + 5 = 12
- Find value of one part: £300 ÷ 12 = £25
- Calculate individual shares:
- First share: 3 × £25 = £75
- Second share: 4 × £25 = £100
- Third share: 5 × £25 = £125











