Steven is a professional classical guitar player. He started a small shop to make and sell Spanish guitars. The guitars sell for $800 and the fixed monthly operating costs are as follows:

Rent and utilities	$1,250
Wages and benefits	2,500
Other expenses	490

The variable costs for the guitars is $280

Steven wishes to earn $6,000 of operating profit each month. Calculate the number of guitars Steven will have to sell to achieve the target profit.