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The numerator of a rational number is 7 less than the denominator .If the denominator is increased by 9 and the numerator by 2, we again get the same rational number. Find the Number

1 Answer

5 votes

Answer:

5/3

Explanation:

Let

Denominator = x

Numerator = x - 7

New

Denominator = x + 9

Numerator = x - 7 + 2

= x - 5

x / x-7 = x -5 / x + 9

Cross product

x * x + 9 = x-7 * x-5

x² + 9x = x²- 5x - 7x + 35

x² + 9x - x² + 5x + 7x - 35 = 0

21x = 35

divide both sides by 21

x = 35 / 21

= 5 / 3

x = 5/3

The rational number is 5/3

User Nicola Desogus
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