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主题:【Help】A Math contest question -- steve
共:💬14 🌺9 新:
My nephew got stuck to a Math contest question. I would highly appreciate it if anyone could give a lift.
How many four-digit positive integers x are there with the property that x and 3x have only even digits? (One such number is x = 8002, since 3x = 24006 and each of x and 3x has only even digits.)
(A) 82 (B) 84 (C) 86 (D) 88 (E) 90
Thanks for all your help!
- 相关回复 上下关系8
🙂【Help】A Math contest question
🙂82 1 枸杞子 字122 2007-02-20 20:48:01
😄选(A),82个 1 煮酒正熟 字411 2007-02-20 19:36:54
🙂A 82 5 随园过客 字217 2007-02-20 19:20:02
🙂right answer. tomy 字0 2007-02-21 06:17:01
🙂太厉害了!花之! 煮酒正熟 字0 2007-02-20 20:04:35
🙂almost right. but it's too tomy 字84 2007-02-20 19:41:14
🙂Wonderful! 喜欢 字0 2007-02-20 19:32:36