Question

There are 20 bags filled with coins that all look alike. The coins in 19 of the bags are authentic and weigh 10 ounces each. The coins in one of the bags are counterfeit and weigh 11 ounces each. With only one weighing on a scale, how can you determine which bag contains the counterfeit coins? This one has me stumped

Answer 1

divide and conquer

Answer 2

hmmm divide what?

Answer 3

it works like this:
divide into 2 groups of 10. One of the group will weigh more than the other. And repeat

Answer 4

thank you will give it a go :-)

Answer 5

Hold on.. i didn't read the question carefully, it said only ONE weighing?

Answer 6

yes only one

Answer 7

uh....

might be impossible

Answer 8

ahh well thanks anyway

Answer 9

Take one coin from 1st bag 2 coins from 2nd bag 3 coins from 3rd bag, 20 coins from 20 th bag.
This will give you 210 coins which should weigh 2100 ounces.
If it weighs 2101 ounces - first bag has the incorrect coins
If it weighs 2102 ounces - second bag, etc.

Answer 10

wow thanks seems too easy lol

Answer 11

it's all right :-)