There are 20 classmates, count them in the order of 1, 2, 3, 4, 5, ..., 20. As a result, the numbers reported by Pippi and Nao Nao are both odd and composite. What is the sum of the two numbers reported by Pippi and Nao Nao?
有20为同学，按1，2，3，4，5，…，20的顺序报数．结果皮皮和闹闹报到的数既是奇数，又是合数．皮皮和闹闹所报的两个数之和是多少．
<gadget id="calculator">9 + 15</gadget>
<output>24</output>

<result>24</result>