California 540 tax

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Marty is employed as a beat writer for a popular media company, and he frequently works from home to finish his deadline work assignments in a timely manner. His office includes a large desk for his computer and monitors, several file cabinets, and a printer/copier area. His office space takes up 120 square feet of a 400 square foot room. Marty lives alone, and his whole house totals 1,500 square feet. His office meets the requirements for an office-in- home deduction. What business percentage would he use when calculating the deduction? a) 26.67% b) 8.00% c) 34.67% d) 30.00%