Answer:
$35,000
Explanation:
net operating income under variable costing would be calculated by preparing income statement under variable costing.
Smith Company
income statement under variable costing system
Sales (7,500 x $40) Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â $300,000
Less Cost of Sales (7,500 x $18) Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â ($135,000)
Contribution                                    $165,000
Less Expenses
selling and administrative expense ($4 x 7,500) Â Â Â Â Â Â ($30,000)
fixed overheads :
manufacturing                                  ($80,000)
selling and administrative expense                 ($20,000)
Net Income                                     $35,000