The formula for the cost per equivalent unit using the weighted$-$average method is

$($Cost of beginning work in process inventory $-$ Cost added during the period$)$ Equivalent units of production

$($Cost of beginning work in process inventory $+$ Cost added during the period$)$ Equivalent units of production

$($Cost of ending work in process inventory $+$ Cost added during the period$)$ Units produced

$($Cost of ending work in process inventory $+$ Cost added during the period$)$ Equivalents units of production