Lesson

Multiplying and dividing by powers of 10 will help us in this lesson. Let's try a problem to practice.

Find the value of 29.34\times100.

Worked Solution

Idea summary

For each power of 10:

- 10
- 100
- 1000
- 10\,000

When we multiply or divide by these values, each digit of the number moves up or down place values according to the number of zeros in the power of 10.

This video looks at how to convert from milligrams (\text{mg}) to grams (\text{g}), or vice-versa, and how to determine whether to multiply or divide by 1000.

Convert 41.9 grams to milligrams.

Worked Solution

Idea summary

To convert from milligrams to grams: \div 1000

To convert from grams to milligrams: \times 1000

This video looks at how to convert between grams (\text{g}) and kilograms (\text{kg}).

Convert 946 grams to kilograms.

Worked Solution

Idea summary

To convert from grams to kilograms: \div 1000

To convert from kilograms to grams: \times 1000

This video looks at how to convert between tonnes (t) and kilograms (kg).

Convert 11 tonnes into kilograms.

Worked Solution

Idea summary

Converting units of mass

When you convert from a larger unit to a smaller unit (e.g. \text{t} to \text{kg}), you multiply.

When you convert from a smaller unit to a larger unit (e.g.\text{g} to \text{kg}), you divide.