I recently went to the shop and purchased 4 items.
Three of the items cost:
$1.50
$3.00
$4.00
There was quite a long queue, and as I was quite bored, I was playing with my pocket calculator while I waited.
Very curiously, the 4 prices added to the same number as I got when I multiplied the 4 prices together.
What was the price of the 4th item?