How do I extract relating values from two separate arrays

I think I've hit a wall, I have an array populated with 2 different values inputted by the user. For example, my script will prompt the user will input some grocery items and the next prompt will ask for the price of that item. This will go on as long as they like.

at the end of the list I would like to be able to extract the most expensive item with the associated price AND the least expensive item with the associated price.