There is a pile of chess pieces, which are divided into three equal parts and one is left; Take out two, divide them into three equal parts, and there is one left: take out two, divide them into three equal parts, and there is one left. How many pieces?

A pile of chess pieces, divided into three equal parts, leaving one.

Take out two, divide them into three equal parts, and leave one.

Take out two, divide them into three equal parts, and leave one.

Push from back to front

Suppose the final situation is 1.

1

1

1

That's four.

Then the second situation is 2.

2

2

1

That's seven

So the first case is 3.5.

3.5

3.5

1

Decimal appearance

The last one out is 1.

1

1

1

Obviously, the last situation can't be 2.

2

2

1

Suppose the final situation is 3.

three

three

1

That is 10.

Then the second situation is 5.

five

five

1

That is 16.

So the first case is 8.

eight

eight

1

That's 25

So there are at least 25.