作者catdreamer (愛做白日夢的貓)
看板GMAT
標題Re: [問題] 請問題目的意思
時間Sat Dec 13 19:40:48 2008
※ 引述《a2518065 (歡樂時光 ^^)》之銘言：
: 題目如下:
: If 10^50-74 is written as an integer in base 10 notation, what is the sum
: of the digits in that integer?
: a.424 b.433 c.440 d.449 e.467
: 請教各位了 = ="
10^50-1
EX
10^1-1=9 one 9
10^2-1=99 two 9
.
.
.
10^50-1= fifty 9
10^50-1-73= 99999...forty-eight 9 + 99-73 = 9*48+2+6=440......(C)
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◆ From: 118.170.136.179
1F：→ kimoqueen:原PO答案是哪個? 12/13 20:06
2F：推 a2518065:感謝大大的講解 答案是C沒錯 感恩 12/13 20:32
3F：推 a2518065:想另外請教某一句話的意思: increase by the same 12/14 01:08
4F：→ a2518065:fraction during each of the two 3-hour period 12/14 01:09
5F：→ a2518065:那個 each of two 3-hour period是什麼意思壓 12/14 01:10