Answers

2015-04-20T11:13:51+05:30
We can assume 1x + 2y +5z= 300 ---> (1)

Total no.of coins , x+y+z = 160 --->(2)

y=3z -->(3)

Subtituting value of (3) in (1) and (2)
1x + (2) * 3z + 5z= 300 
ie; 1x + 6z+5z=300 = x + 11z=300 --> (3)
x+3z+z=160 --> (4)

Considering eqn (3) and (4)

x+11z=300
x+4z=160

then  7z=140 as x cancelled each other.
then z= 20

Now we can calculate rest...

z=20
y = 3z = 60

x+2y+5z=300

then x = 300 -120-100
          = 80

x = 80
y=60
z=20

Solved...
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