Question 1.

Amit has forgotten his 4-digit locker key. He remembers that all the digits are positive integers and are different from each other. Moreover, the fourth digit is the smallest and the maximum value of the first digit is 3. Also, he recalls that if he divides the second digit by the third digit, he gets the first digit.
How many different combinations does Amit have to try for unlocking the locker?

A
2
B
1
C
4
D
5
Rate this Solution
Next Question

Question Explanation

Text Explanation

Let the 4-digit locker key be abcdabcd, where 9a,b,c,d>09 \ge a,b,c,d \gt 0, and they are all unique.

It is given that a3a \le 3 & bc=a\frac{b}{c}=a

It is also given that 'd' is the smallest number.

Case (i): a=1a=1

Not possible, as 'd' is the smallest number, 'a' cannot be 1.

Case (ii): a=2a=2

Then 'd' can take only one value, i.e. d=1d=1 

b=2cb=2c

if c=3c=3, then b=6b=6

if c=4c=4, then b=8b=8

for c 5c\ge\ 5, 'b' will not be a single-digit number.

Hence, two cases are possible, i.e. (2631, 2841).

Case (iii): a=3a=3

'd' can take two values, i.e. d=1d=1 or d=2d=2

& b=3cb=3c

If d = 1, then 'c' can take only one value. i.e. c=2c=2, then b=6b=6

If d = 2, then 'c' cannot take any value.

Hence one case is possible, i.e. (3621)

Amit has to try 3 different combinations. Option (E) is correct.

Video Explanation
No video explanation yet — we're on it and uploading soon!

Master CAT Preparation with Previous Year Papers

Practicing CAT previous year papers is one of the most effective strategies for CAT exam preparation. By solving questions from CAT 2023 qadi-slot-1 and other previous years, you can understand the exam pattern, difficulty level, and types of questions asked in the Common Admission Test.

Why Practice CAT Previous Year Questions?

  • Understand Exam Pattern: CAT previous papers help you familiarize yourself with the question format, marking scheme, and time management required for the actual exam.
  • Identify Important Topics: By analyzing CAT solved questions from multiple years, you can identify frequently asked topics and focus your preparation accordingly.
  • Improve Speed and Accuracy: Regular practice of CAT previous year papers enhances your problem-solving speed and accuracy, which are crucial for scoring well in the exam.
  • Build Confidence: Solving CAT previous year questions builds confidence and reduces exam anxiety by making you comfortable with the exam format.

How to Use CAT Previous Papers Effectively

  1. Solve Under Exam Conditions: Attempt CAT previous year papers in a timed environment to simulate the actual exam experience.
  2. Analyze Your Performance: After solving each CAT previous paper, analyze your mistakes and identify areas that need improvement.
  3. Review Solutions Thoroughly: Study the detailed solutions and explanations provided for each question to understand the correct approach and methodology.
  4. Focus on Weak Areas: Use CAT solved questions to identify your weak areas and dedicate more time to improving them.

CAT Exam Sections Covered

Our comprehensive collection of CAT previous papers covers all three sections of the exam:

  • VARC (Verbal Ability & Reading Comprehension): Practice reading comprehension passages, para jumbles, and other verbal ability questions from CAT previous years.
  • DILR (Data Interpretation & Logical Reasoning): Master DI and LR questions with detailed solutions from CAT previous year papers.
  • QA (Quantitative Ability): Solve arithmetic, algebra, geometry, and other quantitative ability questions from CAT solved papers.

Additional CAT Preparation Resources

Looking for more CAT preparation materials? Explore our comprehensive collection of:

Note: Regular practice of CAT previous year papers, combined with a structured study plan, is essential for achieving a high percentile in the CAT exam. Make sure to solve questions from all sections and review the solutions thoroughly to maximize your preparation effectiveness.

XAT 2026 Full Course - Enroll Now for Best XAT Preparation
CAT LRDI 100 Recorded Course - Master Logical Reasoning and Data Interpretation
HOME
XAT Sankalp Sale
Quant Revision Book
More
YoutubeWhatsapp