All Exams Test series for 1 year @ ₹349 only
Question

The numerator of a fraction is 5 less than its denominator. If 2 is subtracted from the numerator and 2 is added to the denominator, the fraction becomes $\frac{2}{5}$. Find the original fraction.

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is

$\frac{8}{13}$

Solving the Fraction Word Problem

Let the original fraction be represented as $\frac{n}{d}$, where '$n$' is the numerator and '$d$' is the denominator.

Setting Up the Equations

  • According to the first condition, the numerator is 5 less than its denominator: $n = d - 5$
  • The original fraction can be written in terms of the denominator '$d$': $\frac{d-5}{d}$
  • According to the second condition, if 2 is subtracted from the numerator and 2 is added to the denominator, the fraction becomes $\frac{2}{5}$. $\frac{n-2}{d+2} = \frac{2}{5}$

Solving for the Denominator

Substitute the expression for '$n$' from the first condition ($n = d - 5$) into the second equation:

$ \frac{(d-5)-2}{d+2} = \frac{2}{5} $

Simplify the numerator:

$ \frac{d-7}{d+2} = \frac{2}{5} $

Cross-multiply to solve for '$d$':

$ 5(d-7) = 2(d+2) $ $ 5d - 35 = 2d + 4 $

Rearrange the terms to isolate '$d$':

$ 5d - 2d = 4 + 35 $ $ 3d = 39 $ $ d = \frac{39}{3} $ $ d = 13 $

Finding the Numerator and the Original Fraction

Now that the denominator '$d$' is found, calculate the numerator '$n$' using the first condition ($n = d - 5$):

$ n = 13 - 5 $ $ n = 8 $

The original fraction is therefore:

$ \frac{n}{d} = \frac{8}{13} $

Verification

Check if the conditions are met with the fraction $\frac{8}{13}$:

  • Numerator (8) is 5 less than the denominator (13). (13 - 5 = 8) - Condition 1 met.
  • Subtract 2 from the numerator (8 - 2 = 6) and add 2 to the denominator (13 + 2 = 15). The new fraction is $\frac{6}{15}$.
  • Simplify $\frac{6}{15}$: $\frac{6 \div 3}{15 \div 3} = \frac{2}{5}$. - Condition 2 met.

The original fraction is $\frac{8}{13}$.

Was this answer helpful?

Similar Questions

  1. Simplify: $3((\frac{5}{3})x^2 - 28x + 15) - 5(x^2 + 6x - 15)$

  2. Out of four consecutive numbers, the sum of the first two numbers is equal to the fourth number. What is half of the sum of the four numbers?
  3. If $p = 5 - 2\sqrt{6}$, then find the value of $p^2 + \frac{1}{p^2}$
  4. Which of the following number, when added to itself 14 times gives 135 as result?
  5. What is the number of all positive solutions of the equation $|x \times 1| = 0$ ?
  6. The value of $p^2 - 7p + 12$ at $p = 3$ is:
  7. One-sixth of a number exceeds its one-ninth by 100, the number is:
  8. If a positive number is subtracted from its square, we get 812. Find the number.
  9. If $a + b + c = 8$ and both b and c are positive integers greater than zero, then the maximum value 'a' can take is:
  10. Select the term that can replace the question mark (?) in the following equation.

    $(2a^3 - 3)(5a^3 - 2) = 10 a^6 + ? + 6$

Important Questions from Algebric Equations

  1. A group of 630 children is seated in rows for a group photo session. Each row contains three less children than the row in front of it. Which one of the following number of rows is not possible?

  2. The letters L, M, N, 0, P, Q, R, S and T in their order are substituted by nine integers 1 to 9 but not in that order. 4 is assigned to P. The difference between P and T is 5. The difference between N and T is 3. 

    What is the integer assigned to N?

  3. Four persons, Alok, Bhupesh, Chander and Dinesh have a total of Rs. 100 among themselves. Alok and Bhupesh between them have as much money as Chander and Dinesh between them, but Alok has more money than Bhupesh; and Chander has only half the money that Dinesh has. Alok has in fact Rs. 5 more than Dinesh has. 

    Who has the maximum amount of money?

  4. If x=3/2, then the value of 27x3-54x2+36x-11 is

  5. If a+b+c = 6 and ab+bc+ca = 11, then the value of bc(b+c) + ca(c+a) +ab(a+b) +3abc is

Need Expert Advice?
Upcoming Exams
RRB Technician
October 06, 2026
RRB JE
October 27, 2026
RRB ALP
November 03, 2026
Test Series
RRB NTPC img
Railways
RRB NTPC Under Graduate 2026 New Mock Test Series
1580 Tests 2 Tests Free
544 Attempts
4.3(498)
English, Hindi, Telugu +7 More

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App