Answers

2016-01-29T18:36:47+05:30
Let the numbers be 'x' and 'y' 
x+y=30-------(1)
x-y=12--------(2)
Add (1) and (2),
2x=42
x=21
Substitute the value of x in eq(1)
21+y=30
y=30-21
y=9.
Their ratio=x/y=21/9=7/3.
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2016-01-29T19:19:29+05:30
Let the number be x and y
  given, 
           x+y=30     --- (1)
           x-y=12      ---(2)
on adding equation (1) and (2) we get,
x+y+x-y=30+12
x+x=42
2x=42
x=42/2
x=21
after putting the value of x in (1) equation,
21+y=30                      (x+y=30)
y=30-21
y=9
 
the ratio of these two number,
=21:9
=7:3
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