Over- and under-absorption of overheads

The budgeted overhead absorption rate for variable production overheads in department X of Lublin’s factory is £3.00 per direct labour hour and for fixed overhead is £4.50 per direct labour hour. Actual direct labour hours worked exceeded the budget by 500 hours. Requirement If expenditures were as expected for variable and fixed overheads, the total over absorbed overhead for the period would be A £507.50 B £1,500.00 C £2,250.00 D £3,750.00 Answer: When expenditures are as budgeted, but actual and budgeted production activity levels are different, only fixed overhead can be under or over absorbed. Over-absorbed overhead = 500 hrs × £4.50 = £2,250 Variable overhead absorbed = (500 × £3.00) = £1,500 more than budgeted in the original budget. However, variable overhead incurred would be £1,500 more as well, leaving neither under nor over absorbed variable overheads. Why variable overhead absorbed don't have under or over absorbed variable overheads. I think over absorbed variable overheads = 500x4.5+500x3=3750 ---> D and actual > budget --> under why it is over