There are 210 tons of apples in this pile, and (2/7) of this pile of apples are transported 4 times, how many tons of apples are transported on average each time?
这堆苹果有210吨，4次运走这堆苹果的(2/7)，平均每次运多少吨苹果？
<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">(2/7) / 4</gadget>
<output>1/14 = around 0.071429</output>

<gadget id="calculator">210 * (1/14)</gadget>
<output>15</output>

<result>15</result>