for those who are wondering what's going on, and since i have nothing to do, 今天也灌了一天的水, 干点正事吧:
The product of the units digit, the tens digit, and the hundreds digit of the positive integer m is 96. What is the units digit of m?
(1) m is odd.
(2) The hundreds digit of m is 8.
xyz => integer m, the product of x, y and z is 96, and we want to konw what z is
1) m is odd, since m is odd, that means z is odd; since x * y * z = 96 = 2 * 2 * 2 * 2 * 2 * 3, and z is odd, thus z has to be 3, thus 1) by itself is sufficient to know the answer
2) the hundres digit of m is 8 => so x = 8, since 96/8 = 12 = yz, z could be 2, 3, 4, 6, thus 2) by itself is not sufficient to know the answer
thus the anwser is a)作者: UMHIVTDC 时间: 2013-5-30 06:36
感謝解題啦!!作者: doudoucc 时间: 2013-5-31 06:26
It is really a nice question. Thanks for sharing.作者: emilyly 时间: 2013-6-1 07:17
