I was 11 and remember it well but it was a bit confusing at first, 240 pennies to a pound down to 100, the retailers made the most of it by rounding up prices. It was part of the language of our youth, half penny, penny, threepenny bit tanner, florin, half a crown, (two and a kick), 5 bob, ten bob note and those green one pound notes. I don’t remember the white fivers that used to get mentioned but a fiver was a lot of money to a kid in those days.
Think it was two shillings to get in Maine Road as a junior around that time, I’ve still got my season ticket from the 75/76 season and the receipt is for £4.50 for 21 games (blagged a junior ticket!)