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Friday Brain Teaser

Which Bag Contains the Counterfeit Coins?

Imagine you have 10 bags full of coins,
and each bag contains 1000 coins.
One of the bags contains counterfeit coins.
A real coin weighs 1 gram,
while a counterfeit coin weighs 1.1 grams.
Using a scale just one time,
how can you identify which bag contains the counterfeit coins?

V

Place one bag at a time on the scales and when the scales differes by 100 grams you have your counterfeit bag…

I think…

I would think take one coin out of first bag and put on scale, if it ways 1 gram add a coin from second bag to see if scale reads 2 grams or 2.1… continue until you get the point 1 reading… :?:

Pat x

Meant ‘weighs’ not ‘ways’!!!

strudders wrote:
Place one bag at a time on the scales and when the scales differes by 100 grams you have your counterfeit bag...

I think…

Using a scale just one time :smiley:

crazyonions wrote:
Put all the bags on the scales and remove one at a time. When the weight decreases by 1.1, thats yer bag

Using a scale just one time

Everytime you remove a bag you get a differnt reading,
You can only use the scale once for one reading :smiley:

crazyonions wrote:
Put all the bags on the scales and remove one at a time. When the weight decreases by 1.1, thats yer bag

You can only use the scale just one time for one reading

Each time you remove one you get a different reading… not allowed :frowning:

crazyonions wrote:
Put all the bags on the scales and remove one at a time. When the weight decreases by 1.1, thats yer bag

Sorry :frowning: . lost track of which post I was replying to, didn’t mean to correct you twice :cry:

Sorry

Patb wrote:
I would think take one coin out of first bag and put on scale, if it ways 1 gram add a coin from second bag to see if scale reads 2 grams or 2.1... continue until you get the point 1 reading.... :?:

Pat x

You can only use the scale once for one reading

But you are on the right track :mrgreen:

Yeah, you just have a feel with your hand - which one is the heaviest!

You line up the bags and stack up a different quantity of coins from each bag eg, 10, 9, 8, 7 all the way down to 1 coin for bag one. Weigh them. Add up the weight of the coins assming they are all genuine. So, for example if there there is a .3 difference you know that the stack of 3 coins came from the counterfeit bag, and so on.

You put one coin from bag one on the scale, two from bag two, three from bag three, and so on. the amount after the decimal point on the scale tells you which bag has the counterfeit coins. If its 1 gram higher then it’s bag 10 .

Sorry mate, I beat you to it!

crumbs wrote:
You line up the bags and stack up a different quantity of coins from each bag eg, 10, 9, 8, 7 all the way down to 1 coin for bag one. Weigh them. Add up the weight of the coins assming they are all genuine. So, for example if there there is a .3 difference you know that the stack of 3 coins came from the counterfeit bag, and so on.
:uwell done Einstein that one had me completely bamboozled Roisin xo geek:
crumbs wrote:
You line up the bags and stack up a different quantity of coins from each bag eg, 10, 9, 8, 7 all the way down to 1 coin for bag one. Weigh them. Add up the weight of the coins assming they are all genuine. So, for example if there there is a .3 difference you know that the stack of 3 coins came from the counterfeit bag, and so on.

Well Done
YOU get the teasmaid. :sunglasses: … virtual of course :wink:

V

THe winner is CRUMBS :smiley: :smiley: :smiley:

Take 1 coin from the first bag, 2 coins from the second bag etc…
And 10 coins from the tenth bag. Weigh all the picked coins together.
If all the coins weighed the same amount the scale would measure
(1+2+3+4+5+6+7+8+9+10+55 grams).
Since we know that one bag contains counterfeit coins, we can determine which bag it is by reading the scale.
If it reads 55.1 grams we know the counterfeit coins are in bag 1.
If it reads 55.2 grams we know the counterfeit coins are in bag 2 and so on

Yayyyyy!!!

I am so happy I got this because I NEVER get these sorts of puzzles no matter how hard I try…I would like to think that a brain lesion has awoken my logic area in some way?!

Steffi xx :smiley:

…Oh and I have already acquired a teasmade. Can I have a house instead? :wink:

crumbs wrote:
Yayyyyy!!!!!

I am so happy I got this because I NEVER get these sorts of puzzles no matter how hard I try…I would like to think that a brain lesion has awoken my logic area in some way?!

Steffi xx :smiley:

Have a look at the weekend brain teaser:wink:

I’ve lots more :cry: , I know I should get out more :lol: :lol: :lol:

V

Verona wrote:
crumbs wrote:
Yayyyyy!!!!!

I am so happy I got this because I NEVER get these sorts of puzzles no matter how hard I try…I would like to think that a brain lesion has awoken my logic area in some way?!

Steffi xx :smiley:

Have a look at the weekend brain teaser:wink:

I’ve lots more :cry: , I know I should get out more :lol: :lol: :lol:

V

You are not the only one :wink: