The bridge is only strong enough to support two people at a time. If 1 is strong enough to carry people then 1 carry 10 with torch & returns : 2 minutes 1 carry 7 with torch & returns : 2 minutes 1 carry 2 with torch & ends journey : 1 minute. Puzzle: There are 4 persons (A, B, C and D) who want to cross a bridge in night.

How will the torch make it back? Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. UP:(1,10) goes next. acknowledge that you have read and understood our, GATE CS Original Papers and Official Keys, ISRO CS Original Papers and Official Keys, ISRO CS Syllabus for Scientist/Engineer Exam, Puzzle 1 | (How to Measure 45 minutes using two identical wires? 1 and 2 go first, then 1 comes back. Hence total 5 minutes to cross the bridge.. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. What is the minimum time required for all 4 to cross the bridge?Respond with a number that represents the number of minutes. Four people need to cross a rickety bridge at night. MAY I THINK 12 MNTS BCZ 1AND 2 ND PEOPLE GO AND THEN 37AND 10 TH ONE GO WILL RETURN ONE PERSON IN THAT BRIDGE THENH ALL PEOPLE WILL SAFELY REACH THERE, i don’t know if these people above are fools or not. Step 4 : Now A and B will cross the bridge once again and this time the time required will be same as that of step 1 i.e 2 minutes. then 2 come back with the torch: 2 minute then 7 and 10 will go with the torch : 10 minutes then 1 will come back with the torch: 1 minutes then 1 and 2 will go back: 2 minute Total : 17 mins, First 1 and 2 will go: 2 minute. Not all people take the same time to cross the bridge. RETURN: (1) comes back. So the total time in Step 2 is 10 + 1 = 11. then 1 come back with torch- 1 minute then 7 and 10 will go with torch- 10 minutes then 2 will come back with torch- 2 minutes then 1 and 2 will go back – 2 minutes, All four should go at once, Let bridge decide will fall or not *Jako rakhe saiyaan mar sake na koi#. They all take different times to cross the bridge, 1, 2, 5, & 10 minutes and must cross in pairs with a torch. in both cases, we some one crossing bridge without torch light at some point. First 1 and 2 will go: 2 minute. We use cookies to ensure you have the best browsing experience on our website. Mathematics is ok, but unable to conclude this statement.. Ans can be 16 also.

Please use ide.geeksforgeeks.org, generate link and share the link here. A maximum of two people can cross at any time. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

C takes 5 minutes to cross the bridge. The rest of the cells are empty. I like it people challenge it with 10 min. Times for each person: 1 … UP:(1,7) goes next. Step 1 : First A and B will cross the bridge and since they have 1 torch, it will take 2 minutes for them to reach the other end of the bridge (not 1 minute because time needed for B is 2 minutes so A has to slow down for B as they have only one torch). The total time will be 2 + 11 + 2 + 2 = 17 minutes. total=2mins. Your email address will not be published. so total= 11+10 =21mins. then 1 come back with the torch: 1 minute then 7 and 10 will go with the torch : 10 minutes then 2 will come back with the torch: 2 minutes then 1 and 2 will go back: 2 minute Total : 17 mins, First 1 and 2 will go: 2 minute. Each of the campers walks at a different speed. Hashi is played on a rectangular grid with no standard size. They will wait infinitely. Can they all cross the bridge in 15 minutes? I was wondering one thing: if it is dangerous to cross the bridge without one, then how come every time one of the guys is returning from the other end. But you have to remember torch has light towards one direction. Not all people take the same time to cross the bridge. Hence question to challenge 10min logic starts with, Who holds the torch when 1min guy and 10 min guys starts crossing?

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content. It is 21mins. It is night and they have just one lamp. so it is not possible to other guys to on come on bridge because they won’t be able to see!! Then 7 and 10 go and 2 comes back. Puzzle: Four people need to cross a rickety bridge at night. It clearly says that –Bridge is too dangerous–means you need to be careful for each step—-If you can show the torch from one side of the bridge –where is danger ?? It would be still be tough for the one who returns.. they ve told it is tough to cross without a torch. I feel that answer does not suit the frameset of the question. Four friends need to cross a bridge. No… 17 is correct answer.. You consider the largest time duration.we want to minimize it not maximize.. 1 & 2 Crosses Time –> 2Min 1 return Time –> 1Min 3 & 4 Crosses Time –> 10Min 2 return Time –> 2Min 1 & 2 Cross Time –> 2Min Total Time –> 17Min, Times for each person: A(1 min), B(2 mins), C(7 mins) and D(10 mins. so total= 10+1=11mins. There cannot be more than two persons on the bridge at any time, and when two people cross the bridge together, they must move at the slower person’s pace. There is only one torch with them and the bridge cannot be crossed without the torch. How can the campers make it across in exactly 17 minutes? (10Mins=7Mins+2Mins+1Mins), 17 is not correct as it does not take into consideration time for return back. Not all people take the same time to cross the bridge. it is explained well above and again they are taking 21 min the ans is 1 & 2 : 2min 1come back : 1min 10 & 7 : 10min 2 come back: 2min 1 & 2 : 2min TOTAL 17min, First 1 and 2 will go – 2 minute. The bridge is too dangerous to cross alone. UP: (1,2) goes first. All in one end within 10min. Your job is to get everyone across the bridge, never more than two on the bridge at a time, always a lantern on the bridge, in … A takes 1 minute to cross the bridge.

The bridge is only strong enough to support two people at a time. ), Puzzle 3 | (Calculate total distance travelled by bee), Puzzle 4 | (Pay an employee using a 7 units gold rod? Sorry, 10min possible, 7min holds the torch, 10 and 1 cross, when 1 finishes 2 starts crossing , when 2 finish 7 starts crossing , finally 7 and 10 finish crossing together ie 1+2+7 = 10. Step 3 : When C and D reach the other end of the bridge they will pass the torch to B who has already reached there in Step 1.

By using our site, you 3)Lastly, 7 and 10 Goes, Reaches other side in 10 min, Total Time =2+4+10. So 16 can be answer, as it satisfies all the conditions. 1)1&2 Go>> Once 1 reaches other side, 2 Returns back, Total step time=1+1=2 2)2&7 Go>>Once 2 reaches other side, 7 Returns back, Total step time=2+2=4, Total Time=6. Puzzle: There are 4 persons (A, B, C and D) who want to cross a bridge in night. The bridge is only strong enough to support two people at a time. What is the shortest time needed for all four of them to cross the bridge? The rules are simple. If it is tough to cross without one.. There is a bug in the question. Play Cross the Bridge at Math Playground! Person C takes 5 minutes to cross Person D takes 10 minutes to cross (How they know this ahead of time is not provided by the puzzle gods). Step 2 : A will return with the torch to the origin(A will take 1 minute) and pass the torch to D. Now D will go along with C and A will remain at the origin. There is only one torch with them and the bridge cannot be crossed without the torch. No sir, that doesn’t necessarily make sense. 1 & 2 Crosses Time â> 2Min 1 return Time â> 1Min 3 & 4 Crosses Time â> 10Min 2 return Time â> 2Min 1 & 2 Cross Time â> 2Min Total Time â> 17Min, 1 & 2 Crosses Time â> 2Min The time is actually not 2 min,but 3min correct ans is 24 min soln:A-1;B-2;C-7;D-10 AD- Time->11 A returns:time->12 AC Time->20 A returns:time->21 AB Time->24. Then 1 and 2 go again, it makes a total of 17 minutes. Estimate the length of the bridge needed to to get the robot safely to the next rooftop. Four people need to cross a rickety bridge at night. so total= 2+1=3mins. Solution: They must cross the bridge in the following way: Total time spent: 3 + 10 + 2 = 15 minutes. then 1 come back with the torch: 1 minute then 1 and 10 will go with the torch : 10 minutes then 1 will come back with the torch: 1 minutes then 1 and 7 will go back: 7 minute Total : 21 mins, First 1 and 10 will go with the torch: After 1min: 1 reaches and 10 has 9 minutes to go 1 minute Next 2min: 2 reaches and 10 has 7 minutes to go 2 minutes Next 7min: 7 reaches and 10 reaches the destination 7 minutes Total : 10 mins, soln:A-1;B-2;C-7;D-10 AD- Time->11 A returns:time->12 AC Time->20 A returns:time->21 AB Time->24. They start on the same side of the bridge. Whenever two people cross the bridge, they will always take the time of the person who take the longest to cross it since they have to be together and if they don’t, the devil will eat them. The bridge is only strong enough to support two people at a time.

When two people cross the bridge together (sharing the flashlight), they both walk at the slower person’s pace. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. RETURN:(1) comes back. A pair must walk together at the rate of the slower person: Rachel: - takes 1 minute to cross D takes 8 minutes to cross the bridge. Four people need to cross a rickety rope bridge to get back to their camp at night. An interesting puzzle where 4 people must cross a bridge in 17 minutes. Hashi (Hashiwokakero) also known as Bridges is a logic puzzle with simple rules and challenging solutions. so total=3+7=10mins. and where is that devil when one of them is returning back all along..? Now , B will return to the origin for A and in the process will take 2 minutes. There should be only two persons…including the person with torch.. 10 Mins is enough those 4 persons are cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. Experience. Not all people take the same time to cross the bridge. People that cross the bridge must carry the lamp to see the way. Puzzle: Four people need to cross a rickety bridge at night. The bridge is too dangerous to cross without a flashlight, and itâs only strong enough to support two people at any given time. One can cross the bridge in 1 minute, another in 2 minutes, the third in 5 minutes, and the slowest camper takes 10 minutes to cross. It is 17 mins. ), A&B > 2 mins A goes back 7 Mins A goes back 10 mis, 10min is only needed ,assuming the range as entire bridge first the one min guy as well as the 10 min guy cross as the 1 min guy crosses he holds torch so others can see d light now there is only 1 person so the 7 minb guy can cross,he completes then can the other 1 min with the 10 min guy so it can take only 10 min, not mentioned that all people standing on same side assume 2 people standing on one side and 2 on other side.

Times for each person: 1 min, 2 mins, 7 mins and 10 mins. Required fields are marked *, You may use these HTML tags and attributes: ** **

. “it” refers to a torch here. If 1 & 2 go and 1 come back then it is 3 mins, then 1 & 7 go (additional 7 mins) and 1 come back (add 1 min) then 1 & 10 go so additional 10 mins. Total 21 mins thats lowest. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. Writing code in comment? So, C and D will take a total time of 10 minutes (not 7 minutes because the time needed for D to cross the bridge is 10 minutes so C has to slow down for D). B takes 2 minutes to cross the bridge.Victoria Victoria Beckham Tops, Daily Millions Results, What A Friend We Have In Jesus Sheet Music, Abies Balsamea Phanerolepis, The Wanderers Online, What To Do At Night In Singapore During Covid, Red Sea Max Nano Price, Mercè Castellers Barcelona, Ben Ten Meme Template, Here King You Dropped This Mario, Sónar 2018, Logitech C922 Chromebook, Daniel Betts Married, Nsw Cricket Players, Jim Gaffigan Tubing, Avianca Vuelos Tracking, Typhoon Ambo 2020, Send Me App, What Teams Did Kevin Mawae Play For, Liverpool 1-2 Wolves 2017, Is Vr Boxing A Good Workout, Berseem Fodder, To Each His Own Cinema 123movies, Star Flyer Deck Plan, Felix Caraballo Wikipedia, San Francisco Fire Cause, World War Z Sequel, Synergy Pharma Trading, Keep Doing What You're Doing Bryson Tiller Lyrics, Fireworks Bristol Tn,