Things and the gaps between them

The question

A log is sawn into 15 equal pieces.

How many cuts does that take?

The things, or the gaps between them

pieces:15

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Here is what the question gives.
The numbers give you one count straight away: 15 pieces — but is that the answer?
Look at a small row — four dots have three gaps. Whether you add one depends on what is at the ends.
Cuts sit between the pieces, not at the ends: 15 pieces have 15 − 1 = 14 cuts. Break a stick in two and you cut once.

How it works.

01
Here is what the question gives.
02
The numbers give you one count straight away: 15 pieces — but is that the answer?
03
Look at a small row — four dots have three gaps. Whether you add one depends on what is at the ends.
04
Cuts sit between the pieces, not at the ends: 15 pieces have 15 − 1 = 14 cuts. Break a stick in two and you cut once.