The operating income will change if sales increase by 6,000 units by: 108,000.
Using this formula
Change in operating income=(Selling price-Variable cost)×Increase in sales
Let plug in the formula
Change in operating income=($48-$30)×6,000 units
Change in operating income=$18×6,000 units
Change in operating income=108,000 increase
Inconclusion the operating income will change if sales increase by 6,000 units by: 108,000.
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