I have a total of 300 in coins of denomination 1, 2 and * 5. Th
number of 2 coins is 3 times the number of 5 coins. The total number
coins is 160. How many coins of each denomination are with me?
Answers
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
OR
Let the no. of Rs. 5 coins be x
no of Rs. 2 will be 3x
Rs. 1 coin be. 160-3x-x = 160-4x
the amount I have,
from Rs. 2 coins= 3x= 3x2 = 6x
from Rs. 5 coins= x= 5x
from Rs. 1 coin = (160-4x)x1 = 160-4x
Total money Rs.300
6x+5x+160-4x = 300
7x + 160 = 300
7x = 140
x = 20
No. of Rs. 2 Coins = 3x20= 60
No. of Rs. 5 coins = x=20
No. of Re. 1 coin = 160-4x20 =80
And That's The answer !!
Answer:
Total no. of coins = 160
The no. of 5 rs coins be x
The no. of 2 rs coins be 3x
The no. of 5 rs coins be 4x
The no. of coins => 1 coins 160 - ( 3x + x)
= 160 - 4x
Amount of 5 rs coins = 5x
Amount of 2 rs coins = 2x × 2 = 6x
Amount of 1 rs coin = 60 - 4x
.•. -> 5x + 6x + 160 - 4x = 300
-> 11x + 160 - 4x = 300
-> 7x + 160 - 4x + 160 = 300
-> 7x = 140
-> x = 140 / 7 = 20