Multiplying and Dividing Decimals

Multiplying and dividing decimals is two jobs in NSW Year 8 maths: settle the sign with the integer rule, then work out the size (NESA outcome MA4‑FRC‑C‑01). When multiplying, the answer has as many decimal places as the two numbers together, so \(0.06 \times 0.8 = 0.048\).

You will divide by a decimal by first making the divisor a whole number, as in \(23.5 \div 0.05 = 2350 \div 5\), find powers of decimals such as \((-0.2)^3\) and use the order of operations. You will also find missing decimals and count how many whole pieces fit. Changing money for a New Zealand trip, the cost of running a heater and petrol for a drive to Canberra all multiply or divide decimals. It is part of Year 8 Working with Numbers.