question

A company manufactures and sells three products. Budgeted and actual results for the period just ended were as follows.
Product Budgeted sales (units) Budgeted profit per unit Actual sales units Actual profit
x 800 10 700 8
y 1000 6 1200 6
z 600 12 350 16
What was the adverse sales quantity variance?
I calculated the sales quantity variance to be 2800 adverse but this is incorrect. Where have I went wrong. I calculated the variance by comparing the budgeted sales at budgeted profit per unit with the actual sales at budgeted profit per unit. So is my approach incorrect.