BdMO National 2013: Primary 1

Discussion on Bangladesh Mathematical Olympiad (BdMO) National
BdMO
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BdMO National 2013: Primary 1

Unread post by BdMO » Fri Jan 10, 2014 1:11 am

A group of $7$ women takes $7$ days to make $7$ Nokshikatha. How many days will a group of $5$ women take for making $5$ Nokshikatha?

Asif_Himel
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Re: BdMO National 2013: Primary 1

Unread post by Asif_Himel » Sat Jan 18, 2014 5:58 pm

3.857142857
ba 27/7

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Labib
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Re: BdMO National 2013: Primary 1

Unread post by Labib » Sun Jan 19, 2014 11:46 am

Please post your full solution here.
And just to let you know, your answer is not correct.
Think harder.
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.


"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes

Ahanaf Akif Pathan
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Re: BdMO National 2013: Primary 1

Unread post by Ahanaf Akif Pathan » Tue Jan 21, 2014 8:19 pm

Only 7 days

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Labib
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Re: BdMO National 2013: Primary 1

Unread post by Labib » Wed Jan 22, 2014 7:42 pm

Ahanaf Akif Pathan wrote:Only 7 days
@Ahnaf Akif Pathan
Please post your full solution. People actually post problems, because they do not know how to approach or solve the full problem(and sometimes to share good problems).
If they just needed an answer, they would just use a computer. So kindly practice posting full solutions.

Here's a full solution-
If $7$ people need $7$ days to make $7$ katha, then it will take $7.7=49$ days for $1$ person to make $7$ katha (since the workload will $7$ times more)
So it will take that person $\frac{49}7 = 7$ days to sew each katha. ($7$ times less workload)
Therefore it takes $5*7=35$ days for the person to sew $5$ katha. ($5$ times more workload)
Now if we increase the number of sewers to $5$, the workload will be reduced $5$ times.
So, the time needed for $5$ people to sew $5$ katha will be $\frac{35}5 = \boxed 7$ days.
Please Install $L^AT_EX$ fonts in your PC for better looking equations,
Learn how to write equations, and don't forget to read Forum Guide and Rules.


"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." - Sherlock Holmes

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atiab jobayer
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Re: BdMO National 2013: Primary 1

Unread post by atiab jobayer » Fri Jan 24, 2014 9:27 pm

It is only 7days
math champion

MD.MUNTAKIMUL MAHBUB
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Re: BdMO National 2013: Primary 1

Unread post by MD.MUNTAKIMUL MAHBUB » Fri Feb 07, 2014 3:40 pm

BdMO wrote:A group of $7$ women takes $7$ days to make $7$ Nokshikatha. How many days will a group of $5$ women take for making $5$ Nokshikatha?
If 7 people need 7 days to make 7 katha, then it will take 77=49 days for 1 person to make 7 katha (since the workload will 7 times more)
So it will take that person 749=7 days to sew each katha. (7 times less workload)
Therefore it takes 57=35 days for the person to sew 5 katha. (5 times more workload)
Now if we increase the number of sewers to 5 , the workload will be reduced 5 times.
So, the time needed for 5 people to sew 5 katha will be 535=7 days.

prantick
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Re: BdMO National 2013: Primary 1

Unread post by prantick » Sun Jan 11, 2015 11:58 am

need 7 days

Asadullah_iubat
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Re: BdMO National 2013: Primary 1

Unread post by Asadullah_iubat » Mon Oct 02, 2017 2:06 am

7 women make 7 Nokshikatha in 7 days,
So 7 women make 1 Nokshikatha in 7/7 days
So 1 Women make 1 Nokshikatha in (7*7)/7 days or 7 days

Now 5 women make 1 Nokshikatha in 7*5 days
And 5 women make 5 Nokshikatha in (7*5)/5 days or 7 days.

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