Answer:
15%
Step-by-step explanation:
Required rate of return = Net operating income other than income others / Average operating assets
Required Rate of Return = $90,000/$600,000
Required Rate of Return = 0.15
Required Rate of Return = 15%
Thus, the company's required rate of return is 15%
Workings
Return on Investment = Net Profit/Total investments*100
Net income = Return on investment*Total Investments
Net income = $600,000 * 22%
Net income = $132,000
Thus, Net Operating income = Net income - Residual income = $132,000 - $42,000 = $90,000.