A stack of 18 identical blocks is 1.44 metres high. How many blocks make a 3.2 metre stack when there are no gaps?

Explanation

Each block is 1.44 divided by 18, or 0.08 metres high, so 3.2 divided by 0.08 gives 40 blocks. Choosing 32 treats the decimal height almost like a count and does not preserve the fixed height of each block.