the numerator of a fraction is 9 less than its denominator. if 3 is added to its numerator,the new fraction is 1/2 find the original fraction

Sagot :

ANSWER:  3/12 is the original fraction.

Let the denominator be x
the numerator be x - 9  (nine less than the denominator)

If 3 is added to the numerator, the new fraction is 1/2

[tex] \frac{(x-9)+3}{x} = \frac{1}{2} [/tex]

[tex] \frac{x-6}{x} = \frac{1}{2} [/tex]

LCD (Least common denominator is (2)(x)

[tex](2)(x) \frac{(x-6)}{x} = \frac{1}{2} (2)(x)[/tex]

2x - 12 = x
2x - x = 12
x = 12

The original fraction: (Substitute 12 for x)

x-9 
x      

12-9
 
  12
 
3/12    Original fraction.


To check when 3 is added to numerator, the new fraction is 1/2:

 3 + 3  = 1/2
   12

6/12 = 1/2

1/2 = 1/2