There are some digital cards, the numbers written on them are all multiples of 3 or 4, among which cards with multiples of 3 account for (2/3), cards with multiples of 4 account for (3/4), and cards with multiples of 12 account for 20 , how many cards are there in total?
有一些数字卡片，上面写的数都是3或4的倍数，其中3的倍数的卡片占(2/3)，4的倍数的卡片占(3/4)，12的倍数的卡片有20张，问这些卡片共有多少张？
<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

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

<gadget id="calculator">(3/4) - 1</gadget>
<output>-1/4 = around -0.25</output>

<gadget id="calculator">(2/3) + (-1/4)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">20 / (5/12)</gadget>
<output>48</output>

<result>48</result>