Five Chocolate bars cost £11. Three Chocolate Bars and two packs of Biscuits cost £13.6. How much does two Chocolate bars and one pack of biscuits cost.

We know from the question that 5C = £11, where C is number of Chocolate Bars. Therefore C= 11/5 which is £2.20.We also know that 3C + 2B = £13.6 where B is number of packs of Biscuits.Since we know what C is we can show that: 6.60 + 2B = 13.60. If we take 6.60 from both sides we get 2B = 7. So B = £3.50.Therefore 2C + B = 2(2.20) + (3.50) = £7.90. This is the final answer.