The manager of a store selling tea plans to mix a more expensive tea that cost $7 per pound with a less expensive tea that cost $4 per pound to create a hundred forty pound blend that will sell for $6

The manager of a store selling tea plans to mix a more expensive tea that cost $7 per pound with a less expensive tea that cost $4 per pound to create a hundred forty pound blend that will sell for $6.10 per pound. How many pounds of each type of tea are required?