To get a 10% discount, your total spending must be at least £100. For example, if you spend £100, the discount is £10 (10% of £100), so you would pay £90. "

To get a 15% discount, your total spending must be at least £200. For example, if you spend £200, the discount is £30 (15% of £200), so you would pay £170. "

To get a 20% discount, your total spending must be at least £400. For example, if you spend £400, the discount is £80 (20% of £400), so you would pay £320. "