Today I had a 7-year old student for coding lessonsReally smart - and her English really at 7yo+ level - her mum attended as I had requested.
We worked through Hangman and Bulls and Cows and some other games to program.
Finally I gave her this problem because she was showing me some scales:
20 coins same denomination, and presumably same weight.
But one was fake, counterfeit.
We don't know whether it is heavier or lighter.
How many weighings do you need to identify the fake coin?
And is it heavier or lighter?
How do you do this?