In April 2012, a city fully implemented tiered water prices. The basic water price for residents’ domestic water was 2 yuan per cubic meter. Water charges; for parts exceeding 26 cubic meters, water charges will be charged at 1.5 times the basic water price. There are 3 members of Li Ming’s family. In May 2012, they paid a total of 67 yuan for water. Please calculate how much cubic meters of water Li Ming’s family used that month?
2012年4月某城市全面推行阶梯水价，其中居民生活用水基本水价为每立方米2元，具体方案为：用水人口为4人及以下的用户，月用水量不超过26立方米，按基本水价收水费；超过26立方米的部分按基本水价的1.5倍收水费．李明家3口人，2012年5月共交水费67元，请你算一算李明家该月用水多少立方米？
<gadget id="calculator">26 * 2</gadget>
<output>52</output>

<gadget id="calculator">67 - 52</gadget>
<output>15</output>

<gadget id="calculator">2 * 1.5</gadget>
<output>3</output>

<gadget id="calculator">15 / 3</gadget>
<output>5</output>

<gadget id="calculator">26 + 5</gadget>
<output>31</output>

<result>31</result>