top button
Flag Notify
    Connect to us
      Site Registration

Site Registration

In front of you, there are 9 coins. They all look absolutely identical, but one of the coins is fake. However...........

0 votes
639 views

In front of you, there are 9 coins. They all look absolutely identical, but one of the coins is fake. However, you know that the fake coin is lighter than the rest, and in front of you is a balance scale. What is the least number of weightings you can use to find the counterfeit coin?

posted Oct 7, 2020 by Sidharth Malhotra

Share this puzzle
Facebook Share Button Twitter Share Button LinkedIn Share Button

1 Answer (Check Answer ▼)





Similar Puzzles
0 votes

There are 10 bags full of coins out of which one bag is full of fake coins which we don’t know. But you do know that genuine coins weigh 01 gram, but fake weighs 1.1 grams. We have to identify that bag in minimum readings a digital weighing machine.

+1 vote

Two men/women in absolutely identical conditions have two of the exact same water bottles (full of water).
An hour passes, and the temperatures of the water inside the bottles are measured.
The temperature of one of the bottles is noticeably higher than the temperature of the other.
Assuming that the temperature of the setting they were in, as they were both the same, had to do with the change in temperature of the water, why are they different?

0 votes

You have ten stacks of identical looking gold coins.
Nine of the stacks contain all real gold coins, and one of the stacks is made up entirely of fake gold coins.
Each real gold coin weighs exactly 1 gram, while each fake coin weighs exactly 1.1 grams.
Using a scale, how can you determine the stake of fake coins?
Remember, you can use only one measurement.
For example, you stake what you want on the scale to read the weight.
But, you can do this only once, and once the readout is displayed it does not change if you remove any coins.
You can mix the coins up in their stacks, separate them and mark them, whatever.
How do you find out for sure which stake contains the fake gold coins?

0 votes

You have 7 tennis balls that are all identical but one of them is slightly lighter than the others.

Using a balance scale and only two separate weightings, how can you find the light tennis ball?

0 votes

There are 8 identical balls. In that one of the ball is overweight.
There are only two chances to weigh in the weighing machine.
How to find the overweight ball?

...