Find The Heavy Egg
Heard this one from the taxi driver taking us from Esfahan to Tehran.
Find The Heavy Egg
There are 8 identical eggs laying on the table (don’t worry about why).
They are all identical in color, shape, smell, etc.. identical in every way except: one of the eggs weighs just slightly more than all the others.
You can’t tell by feeling it in between your hands.. but you do have a scale (no, it’s not digital). It’s an old-school scale, like this one:
With ONLY 2 WEIGHS – Each weigh can have any number of the 8 eggs on either side. You must determine which eggs you are going to weigh against each other before putting them on the scale.
YOU ONLY GET 2 ATTEMPTS AT WEIGHING THEM…
How do you find the heavy egg?
Leave the answer below, don’t holler it on Facebook, I want to see who can figure it out =)
about 2 years ago
Here's how you do it. On your first weigh you split the eggs up- four on each side. Once you have determined which side weighs more, you then take those four eggs for the second weigh and split them up two on each side. But for the second weigh you are going to start by putting one egg on either side ( see which weighs more, before adding the other 2 eggs (one to each side). If they are equal at first, you can determine the weight lies in one of the other two eggs, and which one can be determined by which side weighs more.
about 2 years ago
Tom – creative answer – that would work!
Let's say there was a rule that you had to choose which eggs you were going to weigh against each other, and put them on the two sides of the scale at the same time.. in your method, we would be looking at 3 separate weighs…
Could you find the heavy egg another way?
about 2 years ago
<div id="riddle-answer">I would divide the eggs in 3 groups. Two groups of 3 eggs each and one with 2 eggs. Now you weigh the two groups of 3 eggs each against each other. There are two possible outcomes. each of which is discussed below
If they come out to be equal then you know that the heavy egg is in the the third group which has 2 eggs. You can now find the heavier egg by weighing the two eggs against each other.
If the two groups of 3 eggs each, weigh unequal, then we pick up any two eggs in the group that weighs heavy. If these two eggs weigh equal then the third egg is the heavy egg. If they don't weigh equal then the one which weighs more is the egg we are looking for!!
What would be more interesting is if you only knew that there is one egg which weighs different, you don't know if it weighs more or less. I wonder if u can do this in 2 steps.
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about 2 years ago
Shantanu – YOU GOT IT! =)
about 1 year ago
The coolest part of this blog entry is the hidden comment. How did you do that?
about 1 year ago
Thanks Andrew — that hidden comment is just CSS, it says: make the text and background black until the mouse is hovering over that text … when the mouse hovers, change the background to grey
Dude, you started your own consultancy in NYC?! – Awesome dude! Wish you the best and let me know if there is anything I can do to help!