Given a:b = c:d, find the missing value
Formula: D = (B × C) / A
A ratio compares two or more quantities. For example, 2:3 means for every 2 units of the first thing, there are 3 units of the second.
If A:B = C:D, then A/B = C/D. This is useful for solving missing values in proportional relationships.
| Operation | Example | Result |
|---|---|---|
| Find missing | 2:3 = 4:? | 6 |
| Simplify | 12:18 | 2:3 |
| Scale up | 2:3 × 5 | 10:15 |
| Divide 100 into 2:3:5 | 100 split by 2:3:5 | 20, 30, 50 |