In 2, 3, 5, 7, 11, take any two different numbers as the numerator and denominator of a fraction respectively, how many such true fractions are there?
在2、3、5、7、11中，任取两个不同的数分别当作一个分数的分子和分母，这样的真分数有多少个．
<gadget id="calculator">4 + 3 + 2 + 1</gadget>
<output>10</output>

<result>10</result>