# Reversed Weighings question [duplicate]

I hope this has an easy answer!

A batch of $$n$$ coins has a single fake coin, which is lighter than the rest.

The idea behind this puzzle is:

What is the largest batch of coins that can have the fake coin identified given $$k$$ weighings?

• Re the above comment, it's probably better to link to the source of the duplicates instead of a question which itself is a duplicate. – boboquack Oct 28 '18 at 0:57
• Fun fact: Jon even commented on the linked dupe question :P – Quintec Oct 28 '18 at 1:14

We can find the fake coin in $$k$$ weighings
From at most $$3^k$$ coins.