need the solution

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 Joined: Mon May 09, 2016 11:18 am
need the solution
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?
 Abdullah Al Tanzim
 Posts: 22
 Joined: Tue Apr 11, 2017 12:03 am
 Location: Dhaka, Bangladesh.
Re: need the solution
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} $...
$ 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

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 Joined: Tue Jun 16, 2015 5:11 am
 Location: Barisal, Bangladesh
Re: need the solution
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 $5151$
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 $5151$
Re: need the solution
I didn't understood the last line.
Wãlkîñg, lõvǐñg, $mīlïñg @nd lìvíñg thě Lîfè
 samiul_samin
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 Joined: Sat Dec 09, 2017 1:32 pm