Question

I have the total of Rupees 300 in coins of denomination Rupee 1, Rupee 2 and Rupee 5. The number of Rupee 2 coins is 3 times the number of Rupee 5 coins. The total number of coins is 160. How many coins of each denomination are with me.

Answer 1

let the no of of 5 rupee coin be x
no. of 2 rupee coin be=3x
no. of 1 rupee coin be y
According to question......................
x+3x+y=160
4x+y=160      mark as 1st
total Rs=300
we have x coin of 5 Rupee ,then Total rupees =5x
similarly......................................................=6x
similarly....................................................=y
total rupees we have=300
11x+y=300
y=300-11x
put the value of y in 1st
4x+300-11x=160
-7x=160-300
-7x=140
x=20
2 rupee coin =3x=60
5 rupee coin=x=20
4x+y=160
80+y=160
y=80
I rupee coin will be=80