Who knows the answers to these brain teasers?

Question

Teaser #!

Four people are on one side of a bridge that they need to cross. It is
dark, there are holes in the bridge surface, and they only have one
flashlight which must travel with them as they cross. To add to their
troubles, the bridge will only support two people at a time.
* Now person #1 can walk cross in 1 minute.

* Person #2 has a limp and can cross in 2 minutes.

* Person #3 has a sprained ankle can cross in 5 minutes.

* Person #4 has a cast on his leg and takes 10 minutes to cross.


No matter how fast a person can cross, he must wait for his companion.
If #1 goes with #2, it takes 2 minutes for them to cross. If number #2
goes with #4, it takes them 10 minutes. The flashlight cannot be thrown,
instead it must be carried and delivered from person to person.



they must cross in 17 minutes before the battery dies. How do they do
it?

Teaser #2

Your job is to measure 45 minutes, if you have only two igniter cords
and matches to light the cords. The two igniter cords have the following
features:

They are twisted from various materials and also different parts can
burn at different speed (e. g. after ten minutes they will not burn at
the same point).
Every cord burns from ignition to the end exactly one hour.
Describe your way of measuring the 45 minutes.

Answer 1

You're supposed to say that they only have one flashlight, and that they can't cross the bridge without the flash light. Otherwise, they can do it in 12 minutes (#3 & #4), then (#1 & #2). With the added constraint of the flash light, someone must come back across. The solution then would be

#1 & #2 cross
then #1 comes back with the flashlight,
#3 & #4 cross (this is the key, the 2 slow guys go together)
then #2 comes back with the flashlight,
#1 & #2 cross


for the second question i would fold the cord into 4 equal lengths and then unfold it until only 1 length is doubled (so that the cord is at 3/4 its original length) and then light them both and it the both finish at the same time it shows 45 minutes have passed.

Answer 2

1 and 2 cross together = 2 minutes
1 returns to the beginning side = 1 minute
3 and 4 cross together = 10 minutes
2 returns to the begining side = 2 minutes
1 and 2 cross together = 2 minutes

Total time = 17 minutes

Light both ends of cord #1 and one end of cord #2
Cord #1 will be burned up in 30 minutes
At that time light the other end of cord #2
Cord #2 will be burned up 15 minutes later

Total time = 45 minutes.

Answer 3

to the first question


1 crosses with 2 and goes back and crosses with 3 and then goes back again and crosses with 4, it takes exactly 17 minutes
1 2 2 minutes
1 3 5 minutes
1 4 10 minutes

(even though we should add time because 1 has to go back across each time)

for the second question i would fold the cord into 4 equal lengths and then unfold it until only 1 length is doubled (so that the cord is at 3/4 its original length) and then light them both and it the both finish at the same time it shows 45 minutes have passed.

Answer 4

permit's see if i will get em a million. sandbox 2. guy overboard 3. I comprehend 4. examining between the traces 5. long undies 6. highway-crossing crossed roads 7. downtown 8. tricycle 9. unlevel 10. won't be able to study that 11. neon easy 12. circles under the eyes thirteen. huge Chair lol 14. roll the cube 15. landing sixteen. 6 ft underground 17. suggestions over count 18. he's by using himself, he's into himself ... 19. backward look 20. existence after dying

Answer 5

1 and 2 cross
1 comes back
3 minutes used

3 and 4 cross
2 comes back
15 minutes used

1 and 2 cross again
17 minutes.

Answer 6

number 1 is the carrier...wait 15 minutes to burn the second one when the first one is through you have your 45 minutes

Answer 7

complex matter. query at a search engine. just that may help!

Answer 8

i only now the first one ummm its impossible