A factory shipped 184 tons of coal, and used an average of 15 tons per day in the first 8 days. The rest is estimated to be used up in 4 days, how many tons can be used per day on average?
某工厂运来184吨煤，前8天平均每天用去15吨．剩下的预计4天用完，平均每天可用多少吨？
<gadget id="calculator">8 * 15</gadget>
<output>120</output>

<gadget id="calculator">184 - 120</gadget>
<output>64</output>

<gadget id="calculator">64 / 4</gadget>
<output>16</output>

<result>16</result>