Ratios compare two quantities: 2 : 3 means that for every 2 of one thing there are 3 of another. They come up in maths class, cooking, mixing cement and sharing profits between partners. This calculator does the three most common ratio jobs.
How to use the ratio calculator
- Choose what you want to do:
- Simplify a ratio such as 12 : 18.
- Find the missing value in a proportion such as 12 : 18 = 10 : ?
- Divide an amount in a ratio, such as ₹10,000 in the ratio 2 : 3.
- Enter a and b, and c when needed.
Formulas
Simplify: divide a and b by their HCF
Proportion: a : b = c : x → x = b × c ÷ a
Divide: first share = amount × a ÷ (a + b); second share = amount × b ÷ (a + b)Examples
- Simplify 12 : 18: the HCF is 6, so 12 : 18 = 2 : 3.
- 12 : 18 = 10 : ? → ? = 18 × 10 ÷ 12 = 15.
- Divide ₹10,000 in 2 : 3: 10,000 × 2 ÷ 5 = ₹4,000 and 10,000 × 3 ÷ 5 = ₹6,000.
FAQ
How do I simplify a ratio with decimals?
Multiply both sides by 10, 100 and so on until they are whole numbers, then divide by the HCF. 1.5 : 2.5 becomes 15 : 25, which is 3 : 5.
How do I divide profit among three partners?
Add the three ratio parts, then give each partner amount × their part ÷ total parts. For 2 : 3 : 5 on ₹1,00,000, the shares are ₹20,000, ₹30,000 and ₹50,000.
What is the difference between ratio and proportion?
A ratio compares two numbers. A proportion says two ratios are equal, such as 2 : 3 = 4 : 6.