A sum of ₹ 64 is made up of 80 coins which ar | vedclass

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(B) Let the number of $100$ paise coins be $x$ and the number of $50$ paise coins be $y$.We have $x + y = 80$ (Total number of coins).The total value

Vedclass · Accepted Answer

$32$

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(B) Let the number of $100$ paise coins be $x$ and the number of $50$ paise coins be $y$.We have $x + y = 80$ (Total number of coins).The total value is $100x + 50y = 6400$ paise (Since ₹ $64 = 6400$ paise).Dividing the second equation by $50$,we get $2x + y = 128$.Subtracting the first equation from this,$(2x + y) - (x + y) = 128 - 80$,which gives $x = 48$.Substituting $x = 48$ into $x + y = 80$,we get $y = 80 - 48 = 32$.Alternatively,using the method of Alligation:Average value per coin $= \frac{6400}{80} = 80$ paise.Using the alligation rule:$100$ paise coins : $50$ paise coins $= (80 - 50) : (100 - 80) = 30 : 20 = 3 : 2$.Number of $50$ paise coins $= \frac{2}{3+2} 	imes 80 = \frac{2}{5} 	imes 80 = 32$.

$A$ sum of ₹ $64$ is made up of $80$ coins which are either $100$ $paise$ or $50$ $paise$ coins. How many coins are of $50$ $paise$?

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