Question

I have a total of rupees 300 in coin of aluminium rs 1, rs 2 and rs 5 . the number of rs 2 , coin is 3times the no. of rs 5 coins . the total no. of coins is 160 . how many coins of rs 5 are with me

Answer 1

let coins be x,y,z
now
3y=z
x+y+z=160
x+y+3y =160
x+4y=160