overheads+variance

The standard fixed production OAR in a factory is $20/machine hour. 1,760 machine hours were worked during the period in which the fixed production overhead variances included: Capacity $3,600 Fav Volume $2,400 Adv What were the budgeted machine hours? a. 1,580 b. 1,880 c. 1,940 d. 1,640 Respected Sir, when I use the capacity variance and work my way backwards the ans I get is 1580: capacity variance =3600F so we've got more hours than expected. with std. OAR of $20 per hr. we've got 3600/20=180 more hours so our budgeted hrs. =actual hours of 1760-180=1580 hrs. then I tried using the volume variance, and work my way backwards the ans I get is 1880: volume variance =2400A so we've produced less hours than expected. with std. OAR of $20 per hr. we've got 2400/20=120 less hours so our budgeted hrs. =actual hours of 1760+120=1880 hrs. To say the least, I'm perplexed. Where have I gone wrong? Please sort me out Sir.