week 5 Tutorial - 1

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[preetam.ind]

Got it, nice way to explain !
Thankyou!
(6*5*4)*4 is correct answer.

[logx]

Sorry, this is wrong women possible combination = 4*3*2 similar to men

[prabhakararao]

the answer is 4C3*(6C3*3!) OR (4C3*3!)*6C3
the 3! comes to highlight the importance of order while matching men or women . We must give importance to either women or men, if we give importance of order to both, we will get same couples more number of times, giving us wrong answer.

[muralikrishna]

This guy is beating around the bush. He himself seems unclear and somehow manages to arrive at an answer. Please change this instructor. The method used by this guy is not consistent with Professor Usha mam's method of teaching. He is complicating it too much.

[shaswat]

The question didnt mention whether we need to include LGBT marriages or not.

[akshaykumart.r.]

Okay I am not that good in math but I think I have an explanation. Please tell me if its right or not.

So what I understood is we should observe the last line in the question. It says, "In how many ways you can guess who the couples are?". Here they have asked for guessing how many 'couples' and not how many 'married men and women'. If we will try to guess married people we are not considering the couples. We are simply guessing who is married and who is not. We would use combination for that, i.e. 6C3*4C3. But since the question asks for the couple. Either men or women should be calculated using permutation and the other with combination. So that we find the couples, i.e. 6P3*4C3 or 6C3*4P3

It will be like we are filling a slot of married people and we fix either men or women first using permutation and use combination to find match for the permuted gender.

[AlphaGama-sj]

I'm unable to understand that why (6×5×4)×4, sir multiply by 4 in 6×5×4 . Can anyone explain that..

[mehulprakash]

They have uploaded it and other tutorials very late.

[mysticstranger]

Hi, I am unable to comprehend the solution.

[cherieback]

This is stupid, first the audio quality is trash. And we are just assuming that all the married couples are straight couples? This is freaking 2021. We need to stop these kinds of stupid assumptions, and grow the hellup.

[v.vidhya]

Very nice explanation. I understood it well. Thanks a lot

[GamersTalks]

You're wrong man, the correct answer is 47