Problem 13:
Sohag and Pias had some coconuts. They sold each coconut at the price which is equal to the number of the total coconuts. Sohag and Pias began to take $20$ Taka each alternately from the obtained money.
Sohag started the process. After a while he found that there was not enough money to take like before. Then he took the remaining money and to make the sharing fair he gave his pen to Pias. If they took $25$ Taka each alternately the situation would be almost same but in that case Sohag Had to give his pencil to Pias. If the pen costs $5$ Taka more than the pencil. What is the price of the pencil? [The costs of pen and pencil are integers]
BdMO National Higher Secondary 2007/13
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samiul_samin
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Re: BdMO National Higher Secondary 2007/13
If the number of cocnuts is $n$ then the obtained money is $n^2$
According to the question $n\geq8$ .Using trial and error method, we get $n=34$.
So $n^2=1156$.if we divide 1156 by 20,we get the remainder 16.
So, the cost of pen is $16/2=8$
The cost of pencil is$8-5=3$
According to the question $n\geq8$ .Using trial and error method, we get $n=34$.
So $n^2=1156$.if we divide 1156 by 20,we get the remainder 16.
So, the cost of pen is $16/2=8$
The cost of pencil is$8-5=3$