Xiaohua's family used an average of 11.5 tons of water per month in the first 5 months, and 80.5 tons of water in the last 7 months. How many tons of water is used on average per month?
小华家1年中，前5个月平均每月用11.5吨，后7个月用水80.5吨．平均每个月用多少吨水？
<gadget id="calculator">11.5 * 5</gadget>
<output>57.5</output>

<gadget id="calculator">57.5 + 80.5</gadget>
<output>138</output>

<gadget id="calculator">5 + 7</gadget>
<output>12</output>

<gadget id="calculator">138 / 12</gadget>
<output>23/2 = around 11.5</output>

<result>23/2 = around 11.5</result>