The dollar can be used once a day. It has to be a dollar’s worth of a product, service or use of a product. For example, A dollar’s worth of a $100 TV would be the life of the TV divided by 100. You would get to enjoy the TV for that amount of time. The product or service is instant and doesn’t require any preparation. It just appears and disappears. Or you could have a TV permanently that is worth one dollar.
Not to brag, but if I made one dollar more per day, I wouldn’t even notice. A dollar ain’t worth a dime these days.
But in answer to your question, ⅒th of a banana.
You can save it.