total revenues needed to break even

total revenues needed to break even
Sheltie Company sells both lamps and clocks at the following per unit data:
Unit Data
Lamps
Clocks
Selling price
$75
$45
Variable costs
48
30
Contribution margin
$27
$15
Sales mix
3
1
Assuming $312,000 fixed costs, how many lamps and clocks should Sheltie Company sell to break even?
Lamps
Clocks
9,600
3,200
9,750
3,250
12,000
4,000
12,900
4,300