Zhao Dong miscalculated 10*(□+0.7) as 10*□+0.7. How far is his calculated result from the correct answer?
赵东把10*(□+0.7)错算成10*□+0.7，他计算的结果与正确答案相差多少？
<gadget id="calculator">10 * 0.7</gadget>
<output>7</output>

<gadget id="calculator">7 - 0.7</gadget>
<output>6.3</output>

<result>6.3</result>