Question 858157
 The sum of three numbers is 3. The sum of twice the first number, 3times the second number, and 4times the third number is 7. The difference between 5 times the first number and the second number is 16. Find the three numbers.
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let x=1st number
let y=2d number
let z=3rd number
..
x+y+z=3
2x+3y+4z=7
5x-y=16
..
4x+4y+4z=12
2x+3y+4z=7
subtract
2x+y=5
5x-y=16
add
7x=21
x=3
y=5-2x=-1
z=3-x-y=1
...
check:
x+y+z=3-1+1=3
2x+3y+4z=6-3+4=7
5x-y=15-(-1)=16
..
1st number=3
2nd number=-1
3rd number=1