## Multiplication and GST calculations, the Angus MacPorridge method

GST (Goods and Services Tax) is charged at the rate of 15% in New Zealand. 15% is the same as 15/100 as a fraction or 0.15 as a decimal. To calculate how much GST has to be added you need to multiply the cost by 0.15. This is then added to give the GST inclusive […]