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The numerator of a rational number is greater than its denominator by 3. If the new number becomes 13/4 when the numerator is tripled and the denominator is decreased by23, find the original number.

User Mattias S
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1 Answer

3 votes

Answer:

Explanation:

Let x represent the numerator and y represent the denominator.

The numerator of a rational number is greater than its denominator by 3. It means that

x = y + 3

If the new number becomes 13/4 when the numerator is tripled and the denominator is decreased by 23, it means that

3x/(y - 23) = 13/4

Cross multiplying, it becomes

3x × 4 = 13(y - 23)

12x = 13y - 299- - - - - - - - - - -1

Substituting x = y + 3 into equation 1, it becomes

12(y + 3) = 13y - 299

12y + 36 = 13y - 299

13y - 12y = 36 + 299

y = 335

x = y + 3 = 335 + 3

x = 338

The original number is 338/335

User Patrick Cullen
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