Variance

Suppose that a company plans to produce 1,000 units of product E during August 20X3. The expected time to produce a unit of E is five hours, and the budgeted fixed overhead is $20,000. The standard fixed overhead cost per unit of product E will therefore be as follows. 5 hours at $4 per hour = $20 per unit Actual fixed overhead expenditure in August 20X3 turns out to be $20,450. The labour force manages to produce 1,100 units of product E in 5,400 hours of work. Hi sir, I was practicing this question and the workings showed that we need to divide 20,000 / 1000. Is this to calculate OAR? Since its budgeted overhead / planned activity? Thanks :)