Answer:
$165,500
Explanation:
Given that,
Sales (4,900 × $90) = $ 441,000 
Cost of goods sold (4,900 × $38) = 186,200 
Gross margin = $ 254,800 
Selling and administrative expenses = $75,000 
Net income = $ 179,800 
Production costs per tennis racket total = $38
Variable production cost = $25
Fixed production cost = $13
Units produced = 6,000
Contribution margin:
 = Sales - Variable production costs
= $441,000 - (4,900 × 25)
= $441,000 - $122,500
= $318,500
Fixed costs = Fixed production costs + Selling and administrative expenses
                    = ($13 × 6,000) + $75,000
                    = $78,000 + $75,000
                    = $153,000
Net income under variable costing:
= Contribution margin - Fixed costs
= $318,500 - $153,000
= $165,500