Q73. Question is given followed by two Statements I and
II. Consider the Question and the Statements. Age of each of P and Q is less than 100 years but more than 10 years. If you interchange the digits of the age of P, the number represents the age of Q. Question : What is the difference of their ages? Statement-I : The age of P is greater than the age of Q. Statement-II : The sum of their ages is 11/6 times their difference.
Which one of the following is correct in respect of the above Question and the Statements?
Detailed Solution
Let the age of P be 10x + y and the age of Q be 10y + x, where x and y are digits from 1 to 9 (since ages are >10 and <100). We need to find the absolute difference |P-Q|. **Statement I: The age of P is greater than the age of Q (P > Q).** 10x + y > 10y + x => 9x > 9y => x > y.
Possible pairs (x,y) satisfying x>y and x,y are digits (y cannot be 0 as Q would be a single digit): - If x=2, y=1 => P=21, Q=12. Difference = 9. - If x=3, y=1 => P=31, Q=13.
Difference = 18. - If x=3, y=2 => P=32, Q=23. Difference = 9. Since the difference is not unique, Statement I alone is insufficient. **Statement II: The sum of their ages is 11/6 times their difference.** P + Q = (11/6) * |P - Q| (10x + y) + (10y + x) = (11/6) * |(10x + y) - (10y + x)| 11x + 11y = (11/6) * |9x - 9y| 11(x + y) = (11/6) * 9 * |x - y| x + y = (9/6) * |x - y| x + y = (3/2) * |x - y| Since x and y are positive digits, x+y is positive.
For the equation to hold, |x-y| must also be positive, implying x ≠ y. Also, for x+y to be a multiple of 3/2, x-y must be even. This means x and y must have the same parity. If x-y is positive, then x > y.
2(x + y) = 3(x - y) 2x + 2y = 3x - 3y 5y = x. Since x and y are single digits (1-9) and y cannot be 0: - If y=1, then x=5. This gives P = 51 and Q = 15. (P>Q is satisfied, 51>15).
- If y=2, then x=10 (not a single digit). No other solutions. So, the only unique pair is (x=5, y=1), which means P=51 and Q=15. The difference in their ages = P - Q = 51 - 15 = 36.
This uniquely determines the ages and their difference. Thus, Statement II alone is sufficient. Therefore, the question can be answered by using Statement II alone, but not Statement I alone.
More Data Sufficiency - Number Properties Questions
More Logical Reasoning Questions
Q56. A person walks 100 m straight from his house, turns left and walks 100 m, again turns left and walks...
CQ66. A Question is given followed by two Statements I and II. Consider the Questions and the Statements. ...
DQ67. A Question is given followed by two Statements I and II. Consider the Questions and the Statements. ...
AQ69. A Question if given followed by two Statement I and II. Consider the Question and the Statements. A ...
CQ37. 37. How many times the hour hand and the minute hand coincide in a clock between 10:00 a.m. and 2.00...
AMore from UPSC 2024 CSAT
Q1. 1. Which of the following statements best reflect the most logical and rational inferences that can ...
BQ2. 2. Based on the above passage, the following assumptions have been made : 1. The food distribution m...
AQ3. 3. Which of the following statements best reflects/reflect the most logical and rational inference/i...
CQ4. 4. Based on the above passage, the following assumptions have been made : 1. Fiscal policies of gove...
DQ5. 5. What is the least possible number of cuts required to cut a cube into 64 identical pieces?...
BAce UPSC with AI-powered Practice
LearnPro's test series adapts to your weak topics and shows real analytics.
Explore Courses →