The ratio of number A to number B is 7:4, how much more number A is than number B.
甲数和乙数的比是7：4，甲数比乙数多多少．
<gadget id="calculator">7 - 4</gadget>
<output>3</output>

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

<result>3/4 = around 0.75</result>