Acustomer in a coffee shop purchases a blend of two coffees: kenyan, costing $3.50 a pound, and sri lankan, costing $5.60 a pound. he buys 4 lb of the blend, which costs him $17.15. how many pounds of each kind went into the mixture?

Pounds depending on his money spent are: Kenyan: 6.59 pounds, Sri lankan: 10.55.
Depending on his money spent, he actually bought 1.885 pounds (17.15/9.1), because he spent $17.15 for 4 pounds. (which means that he bought 4 pounds in a discount rate)

I hope it helped you!