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March 28, 2024, 06:57:40 pm

Author Topic: Error  (Read 782 times)  Share 

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vikasarkalgud

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Error
« on: August 27, 2018, 07:00:57 pm »
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Error
« Last Edit: December 17, 2020, 08:06:56 pm by vikasarkalgud »

RuiAce

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Re: Permutations question
« Reply #1 on: August 27, 2018, 09:24:22 pm »
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720360 is way too big... the maximum number of 5 digit numbers you can form using those six digits is \(6^5\) which equals \(7776\). You sure that value is right?

Anyway: Almost right. Yes to the \( ^3P_1\) bit for the even digit. Now the idea is that the even digit you chose must occupy the last digit, leaving you 4 leftover digits to deal with. However you had good intuition, because indeed there's 5 digits that you arrange for the 4 leftover spots. I would write that out as \( 5 \times 4 \times 3\times 2\), instead of \(5!\) (which kinda insinuates that you're also multiplying an extra 1 on the end, even though it doesn't change the final answer).

Other than that, I'd agree with your solution