Direct Proportion

• When solving for best value, either change all the prices to fit 1 item, or find a HCF between the options and change the prices to fit that amount of items
• When solving using integer scaling, find the scale factor and divide both sides to fit the new value, or divide the old values by 1 and multiply them to fit the question.

  e.g.

  108l £125.28 £125.28/108 = 1.16

  | /4 | /4 or 1.16 x 27 = £31.32

  27l £31.32