tough questions
4 posters
Technothlon'17 Prelims Discussion Forum :: Technothlon Paper Discusiion :: Hauts Paper :: THE FINAL ROUND: TRI WIZARD MAZE
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Re: tough questions
I didn't solve 19th.
For 18th
I tried to turn the ropes to make maximum intersection
For 18th
I tried to turn the ropes to make maximum intersection
Human- Posts : 40
Join date : 2017-07-18
Re: tough questions
For the 18th one, I can give you a start but can't explain the whole solution here. The minimum time you can count is 3.25 minutes.
To get the minimum time (least count) 3.25 mins, do this:
Take one rope and light it from both ends. At the same time take the other three ropes and light just one end of each.
When the 1st rope burns completely, it means half an hour is over.
Then light the other end of one rope which has been burning since half an hour.
When this rope burns completely, it means another 15 minutes have passed.
Then light the other end of one rope which has been burning since 45 minutes(half an hour + 15 mins).
When this rope burns completely, it means another 7.5 minutes have passed.
Then light the last rope from the other end which has been burning since 52.5 mins.
This rope will burn completely in another 3.25 mins.
To get the minimum time (least count) 3.25 mins, do this:
Take one rope and light it from both ends. At the same time take the other three ropes and light just one end of each.
When the 1st rope burns completely, it means half an hour is over.
Then light the other end of one rope which has been burning since half an hour.
When this rope burns completely, it means another 15 minutes have passed.
Then light the other end of one rope which has been burning since 45 minutes(half an hour + 15 mins).
When this rope burns completely, it means another 7.5 minutes have passed.
Then light the last rope from the other end which has been burning since 52.5 mins.
This rope will burn completely in another 3.25 mins.
shubham- Posts : 27
Join date : 2017-07-18
Re: tough questions
@shubham but in question it was mentioned we can light rope only at either of the end
paridhi- Posts : 23
Join date : 2017-07-18
Re: tough questions
Yeah that does not mean that you can light only one end of each rope. The English comprehension might be debatable, but there are evidences and indications in the question which tell us that we can light both ends of the rope.
"For example, the time taken to burn one rope if burnt from only one end is 1 hour"..........this statement gives a hint that we can choose to light both ends of the rope.
The statement just means that you can light the rope only at the ends and not somewhere in the middle.
Also if the statement would mean that you can light the rope only at one end, then the answer would be very small, way below 20.
"For example, the time taken to burn one rope if burnt from only one end is 1 hour"..........this statement gives a hint that we can choose to light both ends of the rope.
The statement just means that you can light the rope only at the ends and not somewhere in the middle.
Also if the statement would mean that you can light the rope only at one end, then the answer would be very small, way below 20.
shubham- Posts : 27
Join date : 2017-07-18
Re: tough questions
It might be less than 20 if rods were used instead of ropes.
We can turn the ropes!!
We can turn the ropes!!
Human- Posts : 40
Join date : 2017-07-18
Re: tough questions
He probably means fold but it shouldnt matter because lighting it anywhere other than the end is meaningless, because one segment will almost surely burn faster than the other. So lighting it at one/both ends is the only way to go
Sai1704- Posts : 10
Join date : 2017-07-19
Re: tough questions
No.
I meant overlapping 2 or more ropes by turning them
I meant overlapping 2 or more ropes by turning them
Human- Posts : 40
Join date : 2017-07-18
Technothlon'17 Prelims Discussion Forum :: Technothlon Paper Discusiion :: Hauts Paper :: THE FINAL ROUND: TRI WIZARD MAZE
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