The denominator pf a rational number. is greater than its numerator by 5. If the numerator is increased by 11 and the denominator is descreased by 3 , the numerator obtained is 5/2 . Find the rational number
Answers
- Answer •
‣ Rational number = 4/9
- Explanation •
Given information,
The denominator of a rational number is greater than it's numerator by 5. If the numerator is increased by 11 and the denominator is decreased by 3, the number obtained is 5/2. Find the rational number.
- Denominator = Numerator + 5
- If the numerator is increased by 11 and the denominator is decreased by 3, the number obtained = 5/2
Let,
- Numerator of rational number be x
- So, it's denominator will be (x + 5)
According to the Question,
- If the numerator is increased by 11 and the denominator is decreased by 3, the number obtained = 5/2
Therefore,
➻ (x + 11)/(x + 5 - 3) = 5/2
➻ (x + 11)/(x + 2) = 5/2
By cross multiplication,
➻ 2(x + 11) = 5(x + 2)
➻ 2x + 22 = 5x + 10
➻ 2x - 5x = 10 - 22
➻ -3x = -12
➻ x = -12/-3
➻ x = 12/3
➻ x = 4
- Hence, numerator of the required rational number is 4.
Now,
➻ Denominator = Numerator + 5
➻ Denominator = x + 5
Putting value of ‘x’ in above eqⁿ,
➻ Denominator = 4 + 5
➻ Denominator = 9
- Hence, denominator of the required rational number is 9.
So,
- Rational number •
➻ Numerator/Denominator
➻ 4/9
- Hence, the required rational number is 4/9.
Verification,
- If the numerator is increased by 11 and the denominator is decreased by 3, the number obtained = 5/2
Therefore,
➻ (x + 11)/(x + 5 - 3) = 5/2
➻ (x + 11)/(x + 2) = 5/2
Putting value of ‘x’ in above eqⁿ,
➻ (4 + 11)/(4 + 2) = 5/2
➻ 15/6 = 5/2
➻ 5/2 = 5/2
➻ LHS = RHS
Hence, Verified ✔