4 friends arrive at a narrow bridge in the dead of a pitch-black night with only one flashlight. Looking at the length of the bridge, they determine that each of them can run across it, but in a certain amount of time... 10 minutes, 5 minutes, 2 minutes, and 1 minute, respectively.
Up to 2 people can cross the bridge at any one time, and one person has to hold the flashlight. If two people cross the bridge, they go at the rate of the slowest person.
Get everyone across the bridge in exactly 17 minutes.
2007-02-12 07:39:34 · 10 answers · asked by Anonymous in Entertainment & Music ➔ Jokes & Riddles
Salahuldin... good effort, but nope. It's not the fastest possible way. The fastest possible way takes 17 minutes, not 19.
2007-02-12 08:02:03 · update #1
1 minute person crosses with 2 minute person. (2)
2 minute person comes back. (4)
5 minute person and 10 minute person cross. (14)
1 minute person comes back. (15)
1 minute person and 2 minute person cross. (17)
But why do they need a flashlight? There should be enough lights from the concert for them to be able to see... And also how can one person take one minute and another 10 minutes to cross the same bridge? lol
2007-02-12 08:05:23 · answer #1 · answered by Anonymous · 1⤊ 0⤋
Okay i done a problem exactly like this the other day!
The 10 minutes walker and the 1 minute person walk across together. When they get to the other side the one minute walker walks back with the torch ... so together thats 11 mintues ..x
The 1 minute walker n the 5 minute walker walk across the bridge and when they get back to the other side the one minute walker goes back over again! So thats 17 minutes all together ...xx Huh! O well my method doesnt work!! buti spent this long ttyping it im gunna send it anyway! x Hehe :D x
2007-02-12 08:06:45 · answer #2 · answered by Anonymous · 0⤊ 0⤋
in the event that all of them take different situations then they won't be able to return and forth inclusive of the torch. So....A starts off with the torch AND a rope inclusive of B. while A arrives on the some distance section he waves the torch from section to section and C starts off,retaining the rope to steer him and heading in the direction of the waving torch. . while B arrives he shouts out and D starts in the time of retaining the rope to steer him and heading in the direction of the waving torch. Time 12 minutes. a clean worldwide checklist which merits the factors. Am I good or am I good.
2016-09-29 00:37:37 · answer #3 · answered by Anonymous · 0⤊ 0⤋
The 10 minute person crosses
The 5 minute person crosses
The 2 minute person crosses with the 1 minute person
The 1 minute person could cross with anybody and it'd still work...
right?
2007-02-12 07:46:49 · answer #4 · answered by jus meeee :) 3 · 0⤊ 2⤋
The guy who can cross in one minute crosses with the 10 minute guy. (Time used: 10 Minutes) Then 1 minute goes back (Time used: 11 Minutes). Goes with the 5 minute guy. (Time: 16 Minutes). Goes back (Time: 17 Minutes) Goes with 2 minute guy (Time: 19 minutes)
That's the fastest possible way.
2007-02-12 07:46:54 · answer #5 · answered by Maverick 6 · 0⤊ 3⤋
1 min guy goes with 2 min guy (2 min). 1 min guy goes back, gives the flashlight to the ten min guy (3 min). Ten min guy and five min guy go together (13 min). Then the two minute guy goes back to one min guy (15). Then they both go across together (17 min)
2007-02-12 08:32:42 · answer #6 · answered by The Postulator 5 · 1⤊ 0⤋
I'm the troll who lives under the bridge and NO ONE IS CROSSING IT!!!!
2007-02-12 07:55:20 · answer #7 · answered by Doll 101 6 · 0⤊ 0⤋
Where did u get this ?
2007-02-12 07:53:42 · answer #8 · answered by Lucky 2 · 0⤊ 0⤋
uh..i would have to think for this question~!
2007-02-12 07:45:16 · answer #9 · answered by tz 4 · 0⤊ 1⤋
huh???
2007-02-12 07:46:43 · answer #10 · answered by my deranged mind 3 · 1⤊ 2⤋