Frequently Asked Puzzles in Job Interviews INTRODUCTION SANGHAMESH S VASTRAD

Overview Explanation of logic and code snippets, if necessary Each chapter will be of a particular puzzle Total of 6-7 chapters Pre-requisites : None

The 3 ants Problem

Problem statement 3 ants sitting on three There are corners of a triangle. All ants randomly pick a direction and start moving along edge of the triangle. What is the probability that any two ants don't collide?

Logic Every ant has two choices Hence, total number of possibilities = 2^3 8

Solution All ants move in clockwise or anti-clockwise direction

Answer Therefore, probability they won't collide = 2/8 or Variation Circle or any other shape with only 3 ants

Generalization What if the number of ants is n on a n-sided polygon? Always only 2 solutions possible, i.e, clockwise or anti-clockwise

Generalized solution Probability of not colliding-2/2 Please provide your feedback and rate this course Up Next: 5 Horses Puzzle

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Sanghamesh S Vastrad

University of Toronto

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Abhishek Khandia

a year ago

i want to prepared IT offiicer

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Sehaj Risham

a year ago

u can refer online lectures provided

Sachin Singh

2 months ago

people answering 6 instead of 8 are the ones who left Permutations combinations in class 11,
leave aside Pand C this is basic MAT knowledge..

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ABHILASH C R

6 months ago

what of square has diagonal?

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Kiran Kumar G S

7 months ago

Good explanation, Thank you

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Ruhi

7 months ago

how topossible become 8?

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Mohit Neniwal

3 months ago

every ant has 2 possibilities. so 3 ants having 2*2*2=8

Uday Kumar Reddy

a year ago

if every ant has 2 directions soo we have only 6 possibilities noo

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