If 2 people share a cost of a meal in the ratio of 2: 3 and 1 person pays £52.20. what is the total cost of the meal ?

For this case the first thing we must do is define variables.
 Whe have then:
 x: payment of the person 1
 y: payment of the person 2
 We then have the following system of equations:
 
 We have then that the value of y is:
 
 Then, the cost of the food is:
 
 
 The cost of the food is:
 130.5