Lining Up the Ends Fairly Before You Compare Anything

You will meet this idea in ordinary days. Races begin at a starting line for exactly this reason. An unfair start makes the result meaningless. This is worth learning because an unfair start makes even careful work come out wrong.

Watch for it today, and when you spot it, tell someone what you noticed and how you knew. Ask yourself where else the same idea might be hiding, then go and look.

Watch this carefully, friend. Comparison only works if you start fairly. Both objects must begin at the same line. If one pencil starts an inch ahead of the other, the shorter one can look longer, and your answer will be wrong through no fault of your counting.

Push both ends against a table edge or a wall before you judge. Fair setup comes before fair judgment, in measuring and in most other things.

Try this experiment on purpose. Compare two objects with the ends uneven, then compare them again lined up properly. Seeing yourself get the wrong answer the first way is the fastest cure for ever doing it again. If you get stuck, use your fingers or counters. Good mathematicians use tools.