Review: Comparing and Ordering Two Digit Numbers

This idea walks around your house all day. Order and comparison run libraries, shops, mail routes, and every list that must be searched quickly. This is worth learning because a firm order of checking keeps comparisons reliable. 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.

This idea is simple once you see it. Comparing follows a firm order. Look at the tens first. If the tens differ, the bigger tens digit wins. If the tens match, the ones decide.

Then write the comparison with the correct symbol, pointing its open side at the larger number. Ordering several numbers means comparing again and again until every number has a place. Try ordering 62, 26, 66, and 22 from least to greatest.

Watch out for rushing. Comparisons feel easy, so people stop checking the tens and start guessing from how the number looks. Slow down for one extra second and check the tens digit deliberately every time. Try a few on your own, and be patient with yourself.