1. I am guessing this is for simple interest. S.I = PRT P for Principal Amount R for Rate T for Time in years I = £4500 × 0.04 × 2 (0.04 = [tex] \frac{4}{100} [/tex] = 4%) I = £360 The total amount will be 4500 + 360 = £4860
2. 20% off, £220 Original price? original price × 0.2 = 220 (0.2 = [tex] \frac{20}{100} [/tex] = 20%) Divide by 0.2 on either sides to find the original price [tex] \frac{original price * 0.2}{0.2} = \frac{220}{0.2} [/tex] 0.2 and 0.2 cancels out original price = £1100
