The total number of 3 digit numbers would be:
First digit can be 5 different ways (It can't be 0)
The second digit can also be 5 ways (it can be 0)
The last digit can be 4 ways.
5 5 4
5*5*4=100
100 Total 3 digit numbers using 0,1,2,3,4,5
Now the number of odd numbers: The ones digit is 1,3, or 5.
The first digit can be 4 different ways (it can't be 0 and can't be the odd digit that is the ones digit)
The second digit can be 4 different ways (it can be 0 but can't be the first digit or the odd digit that is the ones digit)
The last digit can be 3 different ways (1,3, or 5)
4 4 3
4*4*3=48
So there are 48 odd digits.
The number of even digits will be 100-48 = 52
52 even digits
4 4 3
3 digit numbers
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Stuart@KaplanGMAT
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This clearly isn't a GMAT style question, since there are multiple questions built in and no answer choices.muzali wrote:How many number of 3 digit numbers can be formed with the digits 0,1,2,3,4,5 if no digit is repeated in any number? How many of these are even and how many odd?
Please clarify: can the first digit be 0? If we're building a code, we could definitely start with 0. If we're talking about the 3 digit numbers on the number line, then the first digit has to be 1 through 9 (or 1 through 5 in this particular question).
Is this just a question you made up because you're curious, or did you take it from somewhere?
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muzali
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I was posed this question and was confused about how to approach it. It'd be great if you can explain the thought process for both the casesStuart Kovinsky wrote:This clearly isn't a GMAT style question, since there are multiple questions built in and no answer choices.muzali wrote:How many number of 3 digit numbers can be formed with the digits 0,1,2,3,4,5 if no digit is repeated in any number? How many of these are even and how many odd?
Please clarify: can the first digit be 0? If we're building a code, we could definitely start with 0. If we're talking about the 3 digit numbers on the number line, then the first digit has to be 1 through 9 (or 1 through 5 in this particular question).
Is this just a question you made up because you're curious, or did you take it from somewhere?
1. 0 can be in the hundreds place
2. 0 cannot be in the hundreds place
