问题
问答题
During the four years that Mrs. Lopez owned her car, she found that her total car expenses were $18,000. Fuel and maintenance costs accounted for 
of the total and depreciation accounted for 
of the remainder. The cost of insurance was 3 times the cost of financing, and together these two costs accounted for 
of the total. If the only other expenses were taxes and license fees, then the cost of financing was how much more or less than the cost of taxes and license fees ？
答案
参考答案：
300美元。
解析：
设分期付款费为x，则保险费为3x，根据题意可得：
[*]
税款和执照费用
[*]
[*]
所以分期付款费比税款和执照费少1,200-900=300美元。