Fill in the same number in the two □ of "8.7*□-6.7*□=20" to make the equation true, how much should be filled in the □.
在"8.7*□-6.7*□=20"的两个□里填入相同的数，使等式成立，□里应填入多少．
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<result>10</result>