英语翻译How many distinct composite numbers can be formed by adding 2_英语解答

英语翻译
How many distinct composite numbers can be formed by adding 2 of the first 5 prime numbers?

人气：103 ℃　时间：2020-02-03 08:03:00

解答

把前五个素数两两加起来能组成多少个合数?
前五个素数是：2,3,5,7,11
两两相加分别为：5,7,9,13,8,10,14,12,16,18
其中合数有9,8,10,14,12,16,18七个