Question

I have total of rupees 300 in coins of denomination Rupees 1 rupees 2 rupees and rupees 5 the number of rupees 2 coins is 3 times the number of rupees 5 coins the total number of coins is 160 how many coins of each denomination are with me

Answer 1

let the no. of rs 5 coins be x

& the no. of rs 1 coin be y

& no. of rs 2 coins be 3 x

a.q.t total no. of coins = 160

x + 3x+y = 160

4x + y = 160 eq. 1

again a.q.t total rs = 300

5x + 2(3x) + 1y = 300

11x + y = 300 eq. 2

by elimination method

on subtracting both the equations

4x + y = 160

-11x -y = -300

=-7x =-140

x =20

on putting the the value of x in eq 2

4(20) + y =160

80 + y = 160

y =80

now,

no of rs 2 coins = 3(20)

= 60

no. of rs 5 coins = 20

no. of rs 1 coins=80