Brain Teasers

[Excelestial]

OOoohhhh.,....30/(1/2)...multiply by 2 to cancel the fraction = 30*2 = 60 + 10 = 70. What kind of math did I do originally??? lol

 

[Excelestial]

My wind-up clock says there's a 9am! 0900!!

 

[Excelestial]

Okay...#2 question was lame. Throw that one out.

 

[Gerald Higgins]

Divide the nine balls into 3 sets of 3 balls each. Lets call them A, B & C.

Using the weighing scale compare the weights of A & B.

Two outcomes are possible:

1. The heavier ball is present in one of the sets and hence that set will tip. Once we have identified the set which contains the heavier ball, compare 2 balls from the set. Either one of the 2 is the heavier one... or the 3rd one is.

2. Both A & B have the same weight and hence the scales don't tip. So now we know that the heavier ball is in the 3rd set (C). Compare two balls from C like we did in point 1 and either one of the 2 is heavy or the remaining one is heavy.

I THINK this approach is only guaranteed to work if you know the odd ball is heavier. But the original question says it COULD be lighter.
So three outcomes are possible from the first task.
1) Both A and B have the same weight, and therefore the odd ball is in C.
2) The odd ball is heavier, and in A or B
3) The odd ball is lighter, and in A or B.
I don't see how you can resolve this with a single additional weighing.
I suspect the question has been asked wrongly, it should have said, one ball is definitely heavier.

There is a similar problem about 10 balls, one of which is heavier OR lighter, and you have 3 weighings to find it. This is do-able.

 

[Sandeep Warrier]

Okay...#2 question was lame. Throw that one out.

Lame yes... but perfectly logical

I THINK this approach is only guaranteed to work if you know the odd ball is heavier. But the original question says it COULD be lighter.

lol... once again I attempt to solve stuff without reading it completely

 

[Scott Huish]

7. 3 apples (presumably you still have the other apple)

 

[jgthtrotih]

Hi,

Originally Posted (#25) By RobMatthews:

Two spills make a sea/"C" of wet?
28 WET TO SPILL 40 WET...
I got nothin.

You Are Correct!..Well there are many different answers for this one...

Mine Was: "Its Wet Around The Spill"

Thanks!

 

[steve case]

If my rooster lays an egg in your back yard, whose egg is it?

 

[barry houdini]

Who cares, call the papers, you've got an egg-laying rooster.......

 

[jgthtrotih]

What are the next two letters in this sequence?


O T T F F S S E ==?== ==?==


Thanks!
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