(3/7) of a number is equal to (3/4) of (4/5), find this number.
一个数的(3/7)等于(4/5)的(3/4)，求这个数．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">(3/4) / (3/7)</gadget>
<output>7/4 = around 1.75</output>

<gadget id="calculator">(4/5) * (7/4)</gadget>
<output>7/5 = around 1.4</output>

<result>7/5 = around 1.4</result>