主题：[The Official SAT Question of the Day™] November 29th Saturday

Hint : Recall the following three rules:
I. For a number to be divisible by 3, the digits of the number must add up to a number that is a multiple of 3.
II. For a number to be divisible by 5, the number must end in 5 or 0.
III. For a number to be divisible by 2, the number must be even.
最后由 jasontomonaga 于 2008-11-29 17:52:23编辑

Correct Answer: B

• Here's Why: For a number to be divisible by 5, the number must end in 5 or 0; therefore, 999 is not the answer. For a number to be divisible by 2, the number must be even; therefore, 990 is not the answer since you do not want the answer to be divisible by 2. For a number to be divisible by 3, the digits of the number must add up to a number that is a multiple of 3. For 955, 9 + 5 + 5 = 19, which is not a multiple of 3. For 995, 9 + 9 + 5 = 23, which is also not a multiple of 3. For 975, 9 + 7 + 5 = 21; since 21 is a multiple of 3, it follows that 975 is divisible by 3. So 975 is the answer.
  
• Difficulty: Easy
• Question Type: Standard Multiple Choice
  (Mathematics)