how do you solve this kind of questions between 100-999....

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between 100-999, how many number can be divided by 2, or multiples of 2 ?


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by garuhape » Mon Feb 21, 2011 5:20 am
neilcao wrote:between 100-999, how many number can be divided by 2, or multiples of 2 ?


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between 1 and 10, there are 5 different numbers which can be divided by 2. Thus, there are 5*10 numbers within one hundred numbers which can be divided by 2.

This applies to the numbers starting from 101 to 1000. Therefore, you have 5*10*9. However, you have to add one for the missing 100 and subtract one for the 1000 which should not be included in the range.

Thus, the answer is: 5*10*9+1-1=450

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by Anurag@Gurome » Mon Feb 21, 2011 5:30 am
All even integers between 100 and 999 are divisible by 2.
Number of even integers between 100 and 999 = (999 - 100 + 1)/2 = 450
So, there are 450 even integers between 100 and 999 and hence 450 integers between 100 and 999 can be divided by 2.
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by mk101 » Mon Feb 21, 2011 6:44 am
neilcao wrote:between 100-999, how many number can be divided by 2, or multiples of 2 ?


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The answer is = (No of nos divisible by 2 from 1 to 999) - (No of nos divisible by 2 from 1 to 99)

= 499 -49= 450