Bruce Corporation makes four products in a single facility. These products have the following unit product costs:

	Products
	A		B		C		D
Direct materials	$	15.00	$	10.90	$	11.70	$	11.30
Direct labor		20.10		28.10		34.30		41.10
Variable manufacturing overhead		5.00		3.40		3.30		3.90
Fixed manufacturing overhead		27.20		35.50		27.30		37.90
Unit product cost	$	67.30	$	77.90	$	76.60	$	94.20

Additional data concerning these products are listed below.

	Products
	A		B		C		D
Grinding minutes per unit		4.50		6.00		5.00		4.10
Selling price per unit	$	76.80	$	94.20	$	88.10	$	104.90
Variable selling cost per unit	$	2.90	$	1.90	$	4.00	$	2.30
Monthly demand in units		4,700		4,700		3,700		2,700

The grinding machines are potentially the constraint in the production facility. A total of 54,300 minutes are available per month on these machines.

Direct labor is a variable cost in this company.

How many minutes of grinding machine time would be required to satisfy demand for all four products?