Variable cost variance vs. sales price and volume variance

There is no relationship!! The variances in total (with the exception of the fixed overhead variance, given that this question is looking at contribution) explain the difference between the actual contribution and the budget contribution. The variable cost variance is not given and so must be the missing figure that makes the budget and actual figures reconcile. I really do suggest that you watch my free lectures on variance analysis. You can always expect there to be a lot of questions in the exam asking about variances.