If the number of A is 7 and the number of B is 4, then how much more is the number of A than the number of B?
甲数是7，乙数是4，那么甲数比乙数多多少．
<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>