(3/7)*4 is rewritten as an addition formula.
(3/7)*4改写成加法算式是多少．
<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">(3/7) + (3/7) + (3/7) + (3/7)</gadget>
<output>12/7 = around 1.714286</output>

<result>12/7 = around 1.714286</result>