Factory Overhead Controllable Variance

Venneman Company produced $4,500$ units of product that required $8\mathrm{.}5$ standard hours per unit. The standard variable overhead cost per unit is $$1\mathrm{.}80$ per hour. The actual variable factory overhead was $$71,670.$ Determine the variable factory overhead controllable variance. Enter a favorable variance as a negative number using a minus sign and an unfavorable variance as a positive number.

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