Question 72

How many two-digit numbers, with a non-zero digit in the units place, are there which are more than thrice the number formed by interchanging the positions of its digits?

Name: How many two-digit numbers, with a non-zero digit in the units place, are there which are more than thrice the number formed by interchanging the positions of its digits?
Uploaded: July 3, 2020, 10:15 a.m.
Duration: 2 min 57 s
Description: How many two-digit numbers, with a non-zero digit in the units place, are there which are more than thrice the number formed by interchanging the positions of its digits?

Correct Answer: 6

Solution

Let 'ab' be the two digit number. Where b $$\neq$$ 0.

We will get number 'ba' after interchanging its digit.

It is given that 10a+b > 3*(10b + a)

7a > 29b

If b = 1, then a = {5, 6, 7, 8, 9}

If b = 2, then a = {9}

If b = 3, then no value of 'a' is possible. Hence, we can say that there are a total of 6 such numbers.

Share on Whatsapp Share on Whatsapp

Boost your CAT prep: Take All-India 3 free CAT mock tests with Video solutions

Video Solution

Click on the Email ☝️ to Watch the Video Solution

Create a FREE account and get:

All Quant CAT complete Formulas and shortcuts PDF
35+ CAT previous year papers with video solutions PDF
5000+ Topic-wise Previous year CAT Solved Questions for Free

CAT Quant Questions | CAT Quantitative Ability

CAT Linear Equations Questions CAT Percentages Questions CAT Profit And Loss Questions CAT Probability, Combinatorics Questions CAT Time Speed Distance Questions

CAT DILR Questions | LRDI Questions For CAT

CAT DI with connected data sets Questions CAT Venn Diagrams Questions CAT Table with Missing values Questions CAT Puzzles Questions CAT Routes And Networks Questions

CAT Verbal Ability Questions | VARC Questions For CAT

CAT Para Jumbles Questions CAT Grammar and Sentence Correction Questions CAT Miscellaneous Questions CAT Critical Reasoning Questions CAT Vocabulary Questions

Also Read

CAT Mock Tests

CAT 2025 Course

Free CAT Preparation

CAT Questions

CAT Formulas PDF

CAT Study Material

CAT Score vs Percentile

CAT Percentile Predictor

CAT Sectional Tests

CAT Exam

CAT Prep Videos

CAT Registration

CAT Syllabus 2025

CAT Eligibility Criteria

CAT Admit Card

CAT Score Calculator

CAT 2018 QA Slot 2 Question

How many two-digit numbers, with a non-zero digit in the units place, are there which are more than thrice the number formed by interchanging the positions of its digits?

Video Solution

CAT Quant Questions | CAT Quantitative Ability

CAT DILR Questions | LRDI Questions For CAT

CAT Verbal Ability Questions | VARC Questions For CAT

Also Read

Free CAT Quant Questions

Login to your Cracku account

Hello! 👋

Ready to Unlock Your Success?

Please Enter Your OTP

Please enter the following details

Create a free Cracku account

Get Started with 5000+ Free CAT Questions & Mock Tests with Detailed Solutions!