Year 7 Interactive Maths - Second Edition

Multiplication of a Decimal by a Multiple of a Power of Ten

This suggests that:

• To multiply a decimal by a multiple of a power of 10, we can first multiply the decimal by the multiple; and then multiply by the power of 10.
• Multiplying by a power of 10 requires moving the decimal point one place to the right for each zero in the power of 10.

Example 21

Calculate 9.4 × 30.

Solution:

Alternative way:

Example 22

Calculate 0.84 × 7000.

Solution:

Alternative way: