3 teas and 2 coffees have a total cost of £7.80. 5 teas and 4 coffees have a total cost of £14.20. Work out the cost of one tea and the cost of one coffee.

This is a typical simultaneous equations question. Using the information in the question we can write down two equations in two unknowns (let's say T=tea and C=coffee).(1) 3T + 2C = £7.80(2) 5T + 4C = £14.20First we rearrange (1) to get 2C = £7.80 - 3T and substitute this into (2) to get 5T + 2(7.80-3T) = 14.20. This can solved to give T=£1.40.Then T=1.40 can be substituted into either (1) or (2) to give C=1.80