HMMT 十一月 2014 · 冲刺赛 · 第 4 题
HMMT November 2014 — Guts Round — Problem 4
题目详情
- [ 6 ] How many two-digit prime numbers have the property that both digits are also primes?
解析
- [ 6 ] How many two-digit prime numbers have the property that both digits are also primes? Answer: 4 When considering the 16 two-digit numbers with 2, 3, 5, and 7 as digits, we find that only 23, 37, 53, and 73 have this property.