The ratio of number A to number B is 7:3, and number A accounts for the sum of the two numbers ((())/(())).
甲数与乙数的比是7：3，甲数占两数和的((())/(()))．
<gadget id="calculator">7 + 3</gadget>
<output>10</output>

<gadget id="calculator">7 / 10</gadget>
<output>7/10 = around 0.7</output>

<result>7/10 = around 0.7</result>