In order to encourage residents to save water, the water supply company stipulates that when the water used by each person does not exceed 2 cubic meters per month, the fee is 1.6 yuan per cubic meter, and the part that exceeds 2 cubic meters is charged at 5 yuan per cubic meter. Xiaohong’s family has 3 people. A total of 29.6 yuan was paid for water last month. Please calculate how much cubic meters of water was used by her family last month?
供水公司为鼓励居民节约用水，规定每人每月用水不超过2立方米时，按每立方米1.6元收费，超过2立方米的部分按每立方米5元收费，小红家3口人，上月共交水费29.6元，请你算一算她家上月用水多少立方米？
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">6 * 1.6</gadget>
<output>9.6</output>

<gadget id="calculator">29.6 - 9.6</gadget>
<output>20</output>

<gadget id="calculator">20 / 5</gadget>
<output>4</output>

<gadget id="calculator">6 + 4</gadget>
<output>10</output>

<result>10</result>