A pile of sand and gravel is 70.5 tons, 27.8 tons have been transported away, and the rest has been transported in 7 times. How many tons are transported on average each time?
一堆砂石70.5吨，已经运走了27.8吨，剩下的分7次运完，平均每次运多少吨？
<gadget id="calculator">70.5 - 27.8</gadget>
<output>42.7</output>

<gadget id="calculator">42.7 / 7</gadget>
<output>6.1</output>

<result>6.1</result>