Multiplying metric units

Multiplying metric units

Length

In order to multiply the metric units of length, it is important to know the relationship between the metric units of length. Use the chart of metric units of length to remind yourself the relationship between metric units of length from millimetres to kilometres.

Example 1

Multiply 3 km 604 m 54 cm by 4.

Steps:

1. Arrange the units vertically with the smallest unit on the right and the largest unit on the left

   km	m	cm
   3	604	54
   × 4

2. Multiply from right to left or from the smallest to the largest unit.

3. Multiply by considering the relationship between units of length, for example: 1 km = 1,000 m, and 1 m = 100 cm.

4. Multiply 54 cm by 4 to get 216 cm. Remember 1 m = 100 cm, therefore 216 cm equals to 2 m and 16 cm.

5. Write 16 cm in the centimetres column.

6. Multiply 604 m by 4 to get 2,416 m. Add the 2 m that remained in step 4 to 2,416 m. That is, 2,416 m + 2 m = 2,418 m.

7. Remember 1 km = 1,000 m, therefore 2,418 m equals to 2 km and 418 m.

8. Write 418 m in the metres column.

9. Multiply 3 km by 4 to get 12 km, then add the 2 km that remained in step 7 to 12 km. That is, 12 km + 2 km = 14 km.

10. Write 14 km in the kilometres column.

km	m	cm
3	604	54
× 4
14	418	16

Therefore, the answer is 14 km 418 m 16 cm.