The cost of airshows

[captain61]

I was just looking at a couple of posters i have from past airshows

I had to laugh at the prices
RAF Innsworth show at Staverton 1979

pedestrians £1 YES £1 & children 50p cars £4

5th Great warbirds air show
Adults £4.50 children £1.50 cars free

[G-CPTN]

How much was petrol in 1979?

Answer about £1 a gallon . . . (22p a litre)