Variance Analysis

Hi John, I wonder if you can help with this one…

Michel has the following results.

10,080 hours actually worked and paid costing $8,770

If the rate variance is $706 adverse, the efficiency variance $256 favourable, and 5,000 units
were produced, what is the standard production time per unit?

A 1.95 hours
B 1.96 hours
C 2.07 hours
D 2.08 hours

I worked out the standard labour cost at standard hours (8770 – 706 = 8064)
Then OAR = 8064/10080 = 0.8
Used the OAR and the efficiency variance (£256) to work backwards to get 320 hours then calculated the standard hours for the production which is 10400
Then divided 10400/5000 to get 2.08

I didn’t understand the workings in Kaplan Exam Kit so mine are different, but I feel I’m over complicating it.

Is there a simpler / quicker way to approach questions like this if one comes up in the exam?