Among the positive integers not exceeding 30, how many are multiples of 3 or 4?
不超过30的正整数中，是3的倍数或4的倍数的数有多少个．
<gadget id="calculator">30 / 3</gadget>
<output>10</output>

<gadget id="calculator">30 / 4</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<gadget id="calculator">30 / 12</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">(15/2) - (5/2)</gadget>
<output>5</output>

<gadget id="calculator">10 + 5</gadget>
<output>15</output>

<result>15</result>