When the little sloppy calculates, he regards "a number divided by (5/7)" as "a number multiplied by (5/7)", and the calculated answer is (15/28). What is the correct answer?
小马虎在计算时，把"一个数除以(5/7)"，看成"一个数乘以(5/7)"，结果算出的答案是(15/28)，正确的答案是多少．
<gadget id="calculator">15 / 28</gadget>
<output>15/28 = around 0.535714</output>

<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">(15/28) / (5/7) / (5/7)</gadget>
<output>21/20 = around 1.05</output>

<result>21/20 = around 1.05</result>