Infosys Interview Puzzles

Car Wheels Problem

Puzzle: A car has 4 tyres and 1 spare tyre. Each tyre can travel a maximum distance of 20000 kilometers before wearing off. What is the maximum distance the car can travel. You are allowed to change tyres (using the spare tyre) unlimited number of times. Note: All tyres are used upto their full strength. Read More →

Camel and Bananas Puzzle

Camel and Banana Puzzle

Puzzle:  The owner of a banana plantation has a camel. He wants to transport his 3000 bananas to the market, which is located after the desert. The distance between his banana plantation and the market is about 1000 kilometer. So he decided to take his camel to carry the bananas. The camel can carry at Read More →

Burning Rope Timer Puzzle

Daily Puzzle

Puzzle: A man has two ropes of varying thickness (Those two ropes are not identical, they aren’t the same density nor the same length nor the same width). Each rope burns in 60 minutes. He actually wants to measure 45 mins. How can he measure 45 mins using only these two ropes. He can’t cut Read More →

Grandma and Cake – Logical Puzzle

Puzzle: You are on your way to visit your Grandma, who lives at the end of the valley. It’s her anniversary, and you want to give her the cakes you’ve made. Between your house and her house, you have to cross 5 bridges, and as it goes in the land of make believe, there is a troll under every Read More →

Handshake Problem

Problem: At a party, everyone shook hands with everybody else. There were 66 handshakes. How many people were at the party? This question is asked in Infosys written. Solution: Lets say there are n persons 1st person shakes hand with everyone else: n-1 times(n-1 persons) 2nd person shakes hand with everyone else(not with 1st as Read More →

Riding Against the Wind Puzzle

horse-riding

Problem: A horse rider went a mile in 5 minutes with the wind and returned in 7 minutes against the wind. How fast could he ride a mile if there was no wind? Solution: Most of us will proceed like that if a rider goes a mile in 2 minutes with the wind, and returns Read More →

Probability of getting one rupee coin from bag

Problem: A bag contains (x) one rupee coins and (y) 50 paise coins. One coin is taken from the bag and put away. If a coin is now taken at random from the bag, what is the probability that it is a one rupee coin? Answers: Case I: Let the first coin removed be one Read More →

Probability of picking 2 socks of same color

Problem: There are 6 pairs of black socks and 6 pairs of white socks.What is the probability to pick a pair of black or white socks when 2 socks are selected randomly in darkness. This question was asked in Aamaon. Solution: Ways to pick any 2 socks from 24 socks = 24C2 Ways to pick Read More →

River Crossing Puzzle

River crossing puzzle

Problem: Sailor Cat needs to bring a wolf, a goat, and a cabbage across the river. The boat is tiny and can only carry one passenger at a time. If he leaves the wolf and the goat alone together, the wolf will eat the goat. If he leaves the goat and the cabbage alone together, Read More →

3 Doors and Heaven

3 door and heaven puzzle

Problem: A person dies, and he arrives at the gate to heaven. There are 3 doors in the heaven. One of the door leads to heaven, second one leads to a 1-day stay at hell and then back to the gate and the third one leads to a 2 day stay at hell and then Read More →

How can four employees calculate the average of their salaries without knowing other’s salary

This solution has a limitation that information is partially passed  and there needs some trust level. Salary of A: i Salary of B: j Salary of C: k Salary of D: l A passes to B (i + a) where a is a number that A knows B takes this a passes to C (i Read More →