BdMO National 2012: Higher Sec, Sec, Junior 01, Primary 02

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Moon
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BdMO National 2012: Higher Sec, Sec, Junior 01, Primary 02

Unread post by Moon » Sat Feb 11, 2012 11:19 pm

Problem:
Subrata writes a letter to Ruponti every day (in successive intervals of $24$ hours) from Korea. But Ruponti receives the letters in intervals of $25$ hours. What is the number of the letter Ruponti receives on the $25^{th}$ day?
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Blue Blood Prince
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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by Blue Blood Prince » Sun Feb 12, 2012 12:58 pm

Ruponti receives no letter on the 25^{th} day

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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by nafistiham » Mon Feb 13, 2012 5:43 pm

if the counting starts subrata's sending it is $24^{th}$
but, if it starts with ruponti's recieving, it is $25^{th}$
i am still confused. :?
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
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abdullah al munim
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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by abdullah al munim » Mon Feb 13, 2012 11:03 pm

If the first letter is sent before the 24 th hour,then the number of letters is 24.and if the first letter is sent on the 24th hour then it is 23.

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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by *Mahi* » Tue Feb 14, 2012 3:06 pm

এইটা সম্পর্কে ধনঞ্জয় বিশ্বাসের অমর উক্তি-
"দিন কি $[)$ এইরকম নাকি $(]$ এইরকম?"
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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by nafistiham » Tue Feb 14, 2012 3:15 pm

*Mahi* wrote:এইটা সম্পর্কে ধনঞ্জয় বিশ্বাসের অমর উক্তি-
"দিন কি $[)$ এইরকম নাকি $(]$ এইরকম?"
বুঝলাম না । এইটার সাথে ওইটার সম্পর্ক কি ?
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by *Mahi* » Tue Feb 14, 2012 6:05 pm

প্রশ্নটার অর্থ হইল "দিন" কি ধরণের interval, রাত ১২ টায় open না closed.
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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by nafistiham » Wed Feb 15, 2012 2:54 pm

২৫ তম দিনে কোন চিঠি পাবে না । :oops: :x :cry:
\[\sum_{k=0}^{n-1}e^{\frac{2 \pi i k}{n}}=0\]
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Abid
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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by Abid » Wed Feb 29, 2012 9:43 am

সুব্রত চিঠি পাঠাই ২৪ ঘণ্টা পর মানে ১ দিন পর
রুপন্তি পাই ২৫ ঘণ্টা পর অর্থাৎ {১ + (১/২৪) }

n দিন পর সুব্রত চিঠি পাঠাই আর রুপন্তি পাই {n + (n/24)} দিনে

এভাবে তো ২৫ তম দিনে রুপন্তি যে চিঠি পাই শেতা সুব্রত এর ২৪ তম চিঠি......।/??????????? কিংকর্তব্যবিমুঢ়............

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Re: BdMO National 2012: Higher Sec, Sec, Junior 01, Primary

Unread post by turash » Wed Feb 29, 2012 11:21 am

rupani 25 number chiti ti pay 26 th day er 1am e. 24 number chiti pay tar ager din & ek hour age.

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