- What is a reciprocal?
- It is the number you multiply the first number by to get a product of 1.
- Example: Scale factor from A to B is 3. Scale factor from B to A is 1/3
- 3 x 1/3 = 1
- Definition of Scale Factor
- The ratio of any two corresponding lengths in two similar geometric figures is called as Scale Factor.
- The ratio of the length of the scale drawing to the corresponding length of the actual object is called as Scale Factor
Examples
1. What is 300 m in centimeters?
300 m = 30 000 cm
2. Write 1 cm represents 5 m as a ratio.
* change units: 5 m = 500 cm 1 : 500 as a ratio
3. If a map scale tells you that 1 cm represents 15 km. What is 15 km in centimeters?
Write the answer as a ratio.
15 km = 1 500 000 1: 1 500 000 as a ratio
4. What is 7.5m in centimeters?
7.5 m = 750 cm
5. How many kilometers does 3 750 000 cm represent?
3 750 000 cm = 37.5 km