Let the full price of ticket is 1. When Olivia uses a rail card, the full price of a ticket is reduced by 1/3, then she pays
[tex]1 - \frac{1}{3} = \frac{2}{3} \\ [/tex]
of full price
Now we can find full price of ticket
[tex]27 \div \frac{2}{3} = 27 \times \frac{3}{2} = 40.5 \\ [/tex]
Answer: the full price of ticket is £40.5
