The monetary system that requires a double coincidence of wants is known as the

The monetary system that requires a double coincidence of wants is known as the barter system. In a barter system, goods or services are directly exchanged without the use of money. In order for a trade to occur, both parties must have what the other wants, creating a double coincidence of wants. For example, if you have a cow and want some wheat, you would need to find someone who has wheat and wants a cow. This can be difficult and time-consuming, which is why barter systems are not commonly used in modern economies.