In a sale the price of a blue ray decreases by 60%. The sale price is £18.60. What is the price before the sale?

If the price was decreased by 60%, you ended up paying only 40%.

40% of the original price is 18.60

Letting  x  represent the original price:

   0.40 · x  =  18.60

Dividing both sides by 0.40 --->   x  =  46.50