Question

a purse has only two -rupee and five -rupee coin .The sum of the coin is 36 and the total value of the coin is ₹84 .Find the number of five -rupee coin

Answer 1

let the ₹ 2 coins be ' x ' and ₹ 5 coins be 'y'

sum of the coins = 36

x + y = 36 ---------------eq.(1)

according to the given statement :

total value of the coins = ₹84
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2 ( x ) + 5( y ) = 84

2 x + 5 y = 84 ---------eq.(2)

from eq.( 1 ), we get

x = 36 - y

solve for 'y' :
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put value of ' x ' in eq.(2) , we get

2 ( 36 - y ) +5 y = 84

72 - 2y + 5y = 84

3y = 84 - 72

3y = 12 => y = 4 ,

therefore, number of 5 rupee coins = 4

Answer : ₹ 5 coins = 4 .

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