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Old 08-14-2008, 11:25 AM
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I'm thinking of a number between 1-100...

1/5 and 1/3 of the number are both integers.
there are 9 other integers in between 1/5 and 1/3 (excluding them).

(Easy question for most of you)

Last edited by Obsidantion; 08-17-2008 at 12:23 PM.
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Old 08-14-2008, 11:40 AM
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Quote:
Originally Posted by Obsidantion View Post
I'm thinking of a number between 1-100...

1/5 and 1/3 are both integers.
there are 9 other integers in between 1/5 and 1/3 (excluding them).

(Easy question for most of you)
By definition a fraction is not an integer...
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Old 08-14-2008, 11:48 AM
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I think the OP means 1/3 and 1/5 of the integer.

Well, set up your equation. Let n be this number you're trying to find. So, the difference between \frac{1}{3}n and \frac{1}{5}n should equal to 10 (you want 9 integers between (1/3)n and (1/5)n but when you subtract 2 numbers, you include the number you start with which adds 1 to the number of integers in between them. For example, if you want the number of integers between 6 and 3, it's 2. But 6 - 3 = 3 (one more than 2) because you include 6 ).

So you have your equation: \frac{1}{3}n - \frac{1}{5}n = 10
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Old 09-28-2008, 11:46 PM
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n(2/15) = 10

2n = 150

n = 75
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Old 09-29-2008, 03:57 PM
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Quote:
Originally Posted by Sweed View Post
n(2/15) = 10

2n = 150

n = 75
Right again!
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