When we are asked to do a calculation for either addition, subtraction, multiplication or division, we will often decide whether to carry out the calculation ‘mentally’ or to use a ‘formal’ written ...

Calculate \(3.6 + 14.73\). Make sure that units line up with units, tenths line up with tenths and so on. Use zeros as placeholders if you need to. David is doing some DIY. He buys a \({2}~m\) length ...