Calculate with a simple method: 42*((5/21)-(3/14))/10%.
用简便方法计算：42*((5/21)-(3/14))/10%．
<gadget id="calculator">5 / 21</gadget>
<output>5/21 = around 0.238095</output>

<gadget id="calculator">3 / 14</gadget>
<output>3/14 = around 0.214286</output>

<gadget id="calculator">(5/21) - (3/14)</gadget>
<output>1/42 = around 0.02381</output>

<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/42) / (1/10)</gadget>
<output>5/21 = around 0.238095</output>

<gadget id="calculator">42 * (5/21)</gadget>
<output>10</output>

<result>10</result>