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

Six times the present age of P exceeds the present age of Q by 11 years. After 10 years, three times Q's age will be 27 years less than six times P's age at that time. What is the present age (in years) of Q?

The correct answer is
7

Understanding the Age Problem Details

This problem involves finding the current age of a person named Q. We are given two pieces of information that relate the present ages of two people, P and Q, and their ages after a specific time period (10 years). To solve this, we need to translate these statements into mathematical equations.

Setting Up Algebraic Equations for Ages

Let's denote the present age of P as '$P$' years and the present age of Q as '$Q$' years. We can now translate the given conditions into equations:

  • Condition 1: "Six times the present age of P exceeds the present age of Q by 11 years." This means that $6 \times P$ is 11 more than $Q$. The equation is: $6P = Q + 11$ Rearranging this gives us our first equation: $6P - Q = 11$ (Equation 1)
  • Condition 2: "After 10 years, three times Q's age will be 27 years less than six times P's age at that time." First, let's determine their ages after 10 years: P's age after 10 years = $P + 10$ Q's age after 10 years = $Q + 10$ Now, let's translate the condition: $3 \times (Q + 10)$ is equal to $6 \times (P + 10)$ minus 27. The equation is: $3(Q + 10) = 6(P + 10) - 27$ Let's simplify this equation: $3Q + 30 = 6P + 60 - 27$ $3Q + 30 = 6P + 33$ Rearranging the terms to match the format of Equation 1: $6P - 3Q = 30 - 33$ $6P - 3Q = -3$ (Equation 2)

Solving the System of Equations for Q's Age

We now have a system of two linear equations with two variables ($P$ and $Q$): 1. $6P - Q = 11$ 2. $6P - 3Q = -3$ We can solve this system using the elimination method. Notice that both equations have a '$6P$' term. If we subtract Equation 2 from Equation 1, the '$P$' term will be eliminated.

Subtracting Equation 2 from Equation 1: $ (6P - Q) - (6P - 3Q) = 11 - (-3) $ $ 6P - Q - 6P + 3Q = 11 + 3 $ Combine like terms: $ (-Q + 3Q) + (6P - 6P) = 14 $ $ 2Q = 14 $ Now, solve for $Q$ by dividing both sides by 2: $ Q = \frac{14}{2} $ $ Q = 7 $ So, the present age of Q is 7 years.

Calculating P's Age for Verification

Although the question only asks for Q's age, we can find P's age to verify our answer using Equation 1: $6P - Q = 11$. Substitute $Q = 7$: $ 6P - 7 = 11 $ Add 7 to both sides: $ 6P = 11 + 7 $ $ 6P = 18 $ Divide by 6: $ P = \frac{18}{6} $ $ P = 3 $ So, P's present age is 3 years.

Final Verification of Conditions

Let's check if these ages ($P=3$, $Q=7$) satisfy the conditions given in the problem, especially the second condition after 10 years.

  • Condition 1 Check: $6P = 6 \times 3 = 18$. $Q + 11 = 7 + 11 = 18$. This condition holds true ($18 = 18$).
  • Condition 2 Check (After 10 years): P's age = $3 + 10 = 13$ years. Q's age = $7 + 10 = 17$ years. Three times Q's age = $3 \times 17 = 51$. Six times P's age = $6 \times 13 = 78$. Is $3 \times Q$'s age (51) equal to $6 \times P$'s age (78) minus 27? $78 - 27 = 51$. Yes, $51 = 51$. This condition also holds true.

Both conditions are satisfied with $P=3$ and $Q=7$.

Conclusion: Q's Present Age

Based on the calculations and verification, the present age of Q is 7 years.

Was this answer helpful?

Important Questions from Age

  1. Five times the present age of P exceeds the present age of Q by 29 years. After 8 years, five times Q's age will be 17 years less than seven times P's age at that time. What is the present age (in years) of Q?
  2. 7 years ago, the age of a father was 13 years more than twice his son's age. After how many years, from now, will he be twice his son's age?
  3. If 2 times the mother's age is 26 years more than 4 times her daughter's age, and 3 times the daughter's age is 7 years less than the mother's age, then what is the difference (in years) between the ages of the mother and the daughter?

  4. If 2 times a son's age is added to his father's age, the sum is 36 years. If 2.5 times the father's age is added to the son's age, the sum is 72 years. What is the father's age (in years)?

  5. Two times the present age of P exceeds the present age of Q by 41 years. After 7 years, nine times Q's age will be 24 years less than six times P's age at that time. What is the present age (in years) of Q?

Need Expert Advice?

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