BDMO National Primary 2018/8

Discussion on Bangladesh Mathematical Olympiad (BdMO) National
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nahin munkar
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BDMO National Primary 2018/8

Unread post by nahin munkar » Tue Jan 08, 2019 1:50 pm

From $1$ to $6$ nodes, one can go only right side and downward. From $7$ to $11$ nodes, one can go right side or along the diagonal. If you start from $1$, in how many ways can you reach $12$ ?
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samiul_samin
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Re: BDMO National Primary 2018/8

Unread post by samiul_samin » Thu Jan 10, 2019 12:21 pm

Short answer
$64$
There are always $2$ ways to go from $n$ node to $n+1$ node for both sides.
So,total ways=$2×2×2×2×2 +2×2×2×2×2=64$
If I am not making any mistake. :oops:

Tahjib Hossain Khan
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Re: BDMO National Primary 2018/8

Unread post by Tahjib Hossain Khan » Mon Jan 14, 2019 5:33 pm

it is not needed to go all the upper nodes.....so maybe the answer will not be 64

NABILA
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Re: BDMO National Primary 2018/8

Unread post by NABILA » Tue Jan 15, 2019 7:43 pm

I think it will be 11.
Wãlkîñg, lõvǐñg, $mīlïñg @nd lìvíñg thě Lîfè

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samiul_samin
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Re: BDMO National Primary 2018/8

Unread post by samiul_samin » Wed Jan 16, 2019 9:21 pm

NABILA wrote:
Tue Jan 15, 2019 7:43 pm
I think it will be 11.
Can you post your answer?

NABILA
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Re: BDMO National Primary 2018/8

Unread post by NABILA » Thu Jan 17, 2019 3:13 pm

আয়তটির দৈর্ঘ্য, প্রস্থ বরাবর বিবেচনা করলে দুটি রাস্তা আছে। 1>7>12 & 1>6>12. প্রস্থ দুটিকে বাদ দিলে মোট 9টি খাড়া & বাকা রেখা আছে। এক্ষেত্রে 1×9×1=9. এখন 2+9=11. এটা আমার ধারনা। কদিন আগেই সম্ভাবনা শিখলাম তো তাই :mrgreen:

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samiul_samin
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Re: BDMO National Primary 2018/8

Unread post by samiul_samin » Thu Jan 17, 2019 8:36 pm

NABILA wrote:
Thu Jan 17, 2019 3:13 pm
আয়তটির দৈর্ঘ্য, প্রস্থ বরাবর বিবেচনা করলে দুটি রাস্তা আছে। 1>7>12 & 1>6>12. প্রস্থ দুটিকে বাদ দিলে মোট 9টি খাড়া & বাকা রেখা আছে। এক্ষেত্রে 1×9×1=9. এখন 2+9=11. এটা আমার ধারনা। কদিন আগেই সম্ভাবনা শিখলাম তো তাই :mrgreen:
There is no probablity here and I think there is a bug in your solution.
Post no $\fbox{18018}$

NABILA
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Re: BDMO National Primary 2018/8

Unread post by NABILA » Fri Jan 18, 2019 5:25 pm

Actually, I didn't solve it. I have used my দর্শনশক্তি। According the question I still think it will be 11.
Wãlkîñg, lõvǐñg, $mīlïñg @nd lìvíñg thě Lîfè

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