Joel mixes petrol and oil in the ratio 40:1 to make fuel for his leaf blower.
(i) He pours 5 litres of petrol into an empty container to make fuel for his leaf blower. How much oil should be added to the petrol to ensure that the fuel is in the correct ratio?
(ii) Joel has 4.1 litres of fuel left in his container after filling his leaf blower. He wishes to use this fuel in his lawnmower. However, his lawnmower requires the petrol and oil to be mixed in the ratio of 25:1. How much oil should he add to the container so that the fuel is in the correct ratio for his lawnmower?