When landscaping their yard, a couple budgeted 4,200 dollars. The irrigation system is 2,400 dollars and the .?

When landscaping their yard, a couple budgeted 4,200 dollars. The irrigation system is 2,400 dollars and the sod is 1,500 dollars. The rest they will spend on trees and shrubs. Trees each cost 32 dollars and shrubs each cost 4 dollars. Combined they plant a total of 47 trees and shrubs. How many of each did they plant in their yard?