Xiaoming's family spent 52.5 yuan on water in the first quarter of this year. If the price of water is 2.5 yuan per ton, how many tons of water will Xiaoming’s family use on average in the first quarter?
小明家今年第一季度支出水费52.5元．如果每吨水价2.5元，小明家第一季度平均每月用水多少吨？
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