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Homework Help: What Is The Probability Of Picking A 3 Digit Number Divisible By 7

  1. Oct 20, 2005 #1
    What Is The Probability Of Picking A 3 Digit Number Divisible By 7
     
  2. jcsd
  3. Oct 20, 2005 #2
    I'd start by thinking how many possibilities there are, so how many 3 digit integers (whole numbers) are there?

    Then i'd consider how many numbers in this range are divisable by 7, a simpler example which may help you get started would be how many numbers from 1 to 70 are divisable by 7 the answer is just 70/7 = 10.

    Once you've found out how many numbers between the range are divisable by 7, find out what percentage is this amount to the original range?

    I hope this helps (and i hope it's right :tongue2: )
     
  4. Oct 26, 2005 #3
    Mathelord,

    I assume you are looking for whole number answers. Bear with my blue collar logic as I may have your answer. There are 900 possible 3 digit whole numbers. As they are consecutive, simply divide 900 by 7.

    I believe your answer is 128/900 or 14.222%
     
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