need the solution

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kh ibrahim
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need the solution

Unread post by kh ibrahim » Sat Jul 08, 2017 7:31 pm

x takes part in three subjects physics, chemistry and mathematics.Each of the subjects is of 100 marks.How many ways can he obtain 200 out of 300?

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Abdullah Al Tanzim
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Location: Dhaka, Bangladesh.

Re: need the solution

Unread post by Abdullah Al Tanzim » Sun Jul 30, 2017 11:35 am

I think it is $ \frac {102.101}{ 2} $. Notice if you get o in physics then you will have only one way to get 200 marks in the three subjects.if you get 1 in physics then you will have 2 ways and for 2 you will have 3 ways and it will go on for o to 100 ..It forms a series that
$ 1+2+3+.............+101$ and the sum of the series is $ \frac {102.101}{2} $... :)
Everybody is a genius.... But if you judge a fish by its ability to climb a tree, it will spend its whole life believing that it is stupid - Albert Einstein

Golam Musabbir Joy
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Location: Barisal, Bangladesh

Re: need the solution

Unread post by Golam Musabbir Joy » Sat May 19, 2018 8:04 pm

We can solve this problem in this way too.
We will count in how many ways x can miss $100$ marks out of $300$.
let $p$ be the missed marks in physics, $c$ be the missed marks in chemistry and $m$ be the missed marks in mathematics. so we have to find in how many ways $p+c+m=100$ can be possible where $0\leq p,c,m \leq 100$ and the answer is $102\choose 2$ that is $5151$

NABILA
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Re: need the solution

Unread post by NABILA » Mon Jan 14, 2019 9:24 pm

I didn't understood the last line.
Wãlkîñg, lõvǐñg, $mīlïñg @nd lìvíñg thě Lîfè

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samiul_samin
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Re: need the solution

Unread post by samiul_samin » Wed Jan 16, 2019 9:29 pm

NABILA wrote:
Mon Jan 14, 2019 9:24 pm
I didn't understood the last line.
That is a combinatorial notation.
It means in how many ways you can choos $2$ people from $101$ people.
Example:
Ways of choosing $4$ people from $5$ people=$5C4$
:arrow: $(5×4×3×2×1)/(1×2×3×4)$

NABILA
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Re: need the solution

Unread post by NABILA » Thu Jan 17, 2019 2:54 pm

Hmm. Understood.
Wãlkîñg, lõvǐñg, $mīlïñg @nd lìvíñg thě Lîfè

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