Two uneven ropes
There are two ropes which are of different length.
Each rope takes 60 minutes to burn completely when set on fire from one end.
You have to measure 45 minutes of time with the help of this ropes.
You cannot fold the ropes to half or tamper any of them.
The considering point over here is that neither of the ropes can be folded.
Solution:
Take any of the rope , and set it on fire from both the ends. (Lets consider this as rope A)
At the same time, light up the other rope (rope B) from one end.
Now when the first rope (rope A) gets completely burnt, light up the second rope from the other end.
When the second rope completely burns, the entire process from the beginning would have taken 45 minutes.
Explanation:
It would take exactly 30 minutes for the rope A to completely burn when set on fire from both the ends.
At the same time rope B is also set on fire from on end.
So, when rope completely burns, rope B would’ve exactly burnt through it’s half way.
Rope B would still require 30 more minutes to burn completely.
By now we have measured 30 minutes, and now we need 15 more minutes.
So now, light up the other end of rope B.
Rope B would burn completely by 15 minutes.
Thus, 30 + 15 = 45
Take the two ropes and tie them together around halfway of each other. Then take both of the ends of ropes and tie those together around halfway as well. After setting aflame the bottom ends of the rope, just wait until they reach the second knot. 45 Minutes will have passed.
Your Answer
More puzzles to try-
What is the logic behind these ?
3 + 3 = 3 5 + 4 = 4 1 + 0 = 3 2 + 3 = 4 ...Read More »Defective stack of coins puzzle
There are 10 stacks of 10 coins each. Each coin weights 10 gms. However, one stack of coins is defective ...Read More »Which clock works best?
Which clock works best? The one that loses a minute a day or the one that doesn’t work at all?Read More »(Advanced) Cheryl’s Birthday Puzzle
Paul, Sam and Dean are assigned the task of figuring out two numbers. They get the following information: Both numbers ...Read More »Five greedy pirates and gold coin distribution Puzzle
Five puzzleFry ship’s pirates have obtained 100 gold coins and have to divide up the loot. The pirates are all ...Read More »Magical flowers!!
A devotee goes to three temples, temple1, temple2 and temple3 one after the other. In front of each temple, there ...Read More »Tuesday, Thursday what are other two days staring with T?
Four days are there which start with the letter ‘T‘. I can remember only two of them as “Tuesday , Thursday”. ...Read More »How could only 3 apples left
Two fathers took their sons to a fruit stall. Each man and son bought an apple, But when they returned ...Read More »How Many Eggs ?
A farmer is taking her eggs to the market in a cart, but she hits a pothole, which knocks over ...Read More »HARD MATHS – How much faster is one train from other Puzzle
Two trains starting at same time, one from Bangalore to Mysore and other in opposite direction arrive at their destination ...Read More »Most Analytical GOOGLE INTERVIEW Question Revealed
Let it be simple and as direct as possible. Interviewer : Tell me how much time (in days) and money would ...Read More »Lateral thinking sequence Puzzle
Solve this logic sequence puzzle by the correct digit- 8080 = 6 1357 = 0 2022 = 1 1999 = ...Read More »How did he know?
A man leaves his house in the morning to go to office and kisses his wife. In the evening on ...Read More »Pizza Cost Math Brain Teaser
Jasmine, Thibault, and Noah were having a night out and decided to order a pizza for $10. It turned out ...Read More »Which letter replaces the question mark
Which letter replaces the question markRead More »Which room is safest puzzle
A murderer is condemned to death. He has to choose between three rooms. The first is full of raging fires, ...Read More »Richie’s Number System
Richie established a very strange number system. According to her claim for different combination of 0 and 2 you will ...Read More »Srabon wanted to pass
The result of math class test came out. Fariha’s mark was an even number. Srabon got a prime!! Nabila got ...Read More »Become Normal!!
Robi is a very serious student. On the first day of this year his seriousness for study was 1 hour. ...Read More »Sakib Knows The Number!
Ragib: I got digits of a 2 digit number Sakib: Is it an odd? Ragib: Yes. Moreover, the sum of ...Read More »