CAT Quantitative Aptitude Questions | CAT Permutation and Combination Questions

CAT Questions | Permutation Probability | 3 Digit numbers > 500
× CAT Questions

CAT Quantitative Aptitude
HCF and LCM Factors Remainders Factorials Digits Ratios,Mixtures;Averages Percents; Profits; SICI Speed & Time; Races Logarithms and Exponents Pipes,Cisterns; Work,Time Set Theory Geometry Coordinate Geometry Mensuration Trigonometry Linear & Quadratic Equations Functions Inequalities Polynomials Progressions
CAT Verbal
Para Jumble Sentence Correction Sentence Elimination Paragraph Completion Reading Comprehension Critical Reasoning Word Usage Para Summary Text Completion
CAT LR DI
DI LR: Bar Graphs DI LR: Pie Charts DI LR: Multiple Graphs DI LR: Word Problems DI LR: Line Graphs DI LR: Sequencing DI LR: Grid Puzzles DI LR: Math Puzzles DI LR: Visualization DI LR: Other Patterns DI LR: CAT 2017 Cet DI LR: CAT 2017 Rural Survey DI LR: CAT 2017 Happiness DI LR: CAT 2017 Airlines DI LR: CAT 2017 Travel Route DI LR: CAT 2017 Food Delivery DI LR: CAT 2017 Square Layout DI LR: CAT 2017 Team Project DI LR: CAT 2017 Assets DI LR: CAT 2017 Pizza DI LR: CAT 2017 Electives DI LR: CAT 2017 Chess DI LR: CAT 2017 Dorms DI LR: CAT 2017 Tea DI LR: CAT 2017 Friends DI LR: CAT 2017 Security Scan

CAT Online Coaching
CAT Question MenuCAT Questions

The question is from Permutation and Combination. Another question which combines number theory with combinatorics. Our task is to find number of 3 digits numbers which satisfies the given condition. This section hosts a number of questions which are on par with CAT questions in difficulty on CAT Permutation and Combination, and CAT Probability.

Question 33: How many 3-digit numbers greater than 500 contain the digit 9 appearing at least once?

  1. 191
  2. 176
  3. 153
  4. 189

2IIM : Best Online CAT Coaching


2IIM's Online CAT Coaching
4000 off on CAT Online Course for CAT 2020.
Vaild till Dec 16th
CAT Online Coaching


Best CAT Coaching in Chennai


CAT Coaching in Chennai - CAT 2020
Starts Sat, December 14th, 2019


Explanatory Answer

Method of solving this CAT Question from Permutation and Combination: Consider this - the digit can appear 1, 2 ir 3 times!!

509, 519... 999 all these numbers have atleast one 9 in them
These put together gives 50 numbers
Now 590,591,..599 atleast has one 9 , but 599 is already included in the first list. Hence 9 numbers.
Similarly for 600-900 series, all put together we get 45 numbers
All numbers from 900 to 999 have a 9 in them but 990-999 are already accounted and also 909,919..999 are accounted.

Hence 81 numbers will have 9 atleast once.
Put together totally 176 numbers have atleast one 9 in them between 500-999.

The question is "How many 3-digit numbers greater than 500 contain the digit 9 appearing at least once?"

Hence the answer is "176"

Choice B is the correct answer.

 


CAT Preparation Online | CAT Permutation and Combination; Probability Videos On YouTube


Other useful sources for Permutation and Combination Questions | Probability Questions


CAT Questions | CAT Quantitative Aptitude

CAT Questions | CAT DILR

CAT Questions | Verbal Ability for CAT


Where is 2IIM located?

2IIM Online CAT Coaching
A Fermat Education Initiative,
58/16, Indira Gandhi Street,
Kaveri Rangan Nagar, Saligramam, Chennai 600 093

How to reach 2IIM?

Phone: (91) 44 4505 8484
Mobile: (91) 99626 48484
WhatsApp: WhatsApp Now
Email: prep@2iim.com