Thursday, October 18, 2007


I found these brainteasers from a website. This is just to check if my brain is still working.

Question 1:
Two trains 200 km from each other are moving at the speed of 50 km/hour towards each other. From one train a fly takes off, flying straight (upon the rails) to the other train at the speed of 75 km/hour, bounces away from it and flies back to the first train. This is repeated till the trains crash into each other and the fly is smashed. What distance is the fly able to fly until its death?(There is a complicated and an easy way to solve this math brain teaser.)

Question 2:
A basket contains 5 apples. Do you know how to divide them to 5 kids so that each one has an apple and one apple stays in the basket?

Question 3:
A girl who was just learning to drive went down a one-way street in the wrong direction, but didn't break the law. How come?

Question 4:
A man lives on the tenth floor of a building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator - or if it was raining that day - he goes back to his floor directly. Otherwise, he goes to the seventh floor and walks up three flights of stairs to his apartment. Can you explain why?(This is probably the best known and most celebrated of all lateral thinking logic puzzles. It is a true classic. Although there are many possible solutions which fit the initial conditions, only the canonical answer is truly satisfying.)

Question 5:
I am looking at somebody's photo. Who is it I am looking at, if I don't have any brothers or sisters and the father of that man on the photo is the son of my father?


If you want more questions, check out the link above. Of the five, I correctly answered four. Not much thinking is required actually.


Francesca said...

No 4 alam ko sagot. Unano, lol

yung payong,dala niya kasi umuulan, pang abot nya sa taas ng numbers ng floors, hehe.
Kung may kasabay siya, may taga pindot siya ng floor number.
korek ako?
Wala daya yan ha? Di ko alam if may sagot sa web links.

lazarus said...

galing mo madamme, ah! eto yung di ko nasagot. he he.

freeze said...

errr, can't read this now else I can't stop analyzing about it. :D

Abaniko said...

Hmm, nakaka-challenge to ah. Let me try:

1. 150 kms? Because given the speeds of the two trains, they will crash into each other in two hours (50+50)+(50+50) = 200 kms. By then, the fly must have flown a total distance of (75+75) kms.

2. The last kid receives his apple still in a basket.

3. She just walked down the one-way road.

4. The man's a midget. (aside from the answer of Francesca, I think I heard of this before).

5. I'm looking at my own photo?

Let me know if my answers are correct or not. :)

lazarus said...

freeze, it won't take you 5 minutes answering all Qs. he he

abaniko, you got 4 out of 5. You're looking at your son's photo.

Abaniko said...

Nakakainis. I was so careless in the last question. Masyadong nagmamadali. But I notice I easily get confused with that kind of questions - the father of the wife's husband of the neighbor's cousin's son's daughter is the son of the daughter of the nephew of the husband's driver, blah, blah.