Putting Three Objects in Order from Shortest to Longest

Think about where you have seen this before. Organizing tools by size, from small screwdriver to large, makes finding the right one much faster. This is worth learning because ordering by size is how people organize almost everything physical. 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.

Here comes a new math idea. Order lengths by comparing two at a time. Find the shortest and set it down first. Compare the two that remain and place them in order.

Now check your line: each object should be a little longer than the one before it. If any pair looks wrong, compare that pair again directly. Ordering three objects is simply comparing twice and then checking your work once.

Here is a check for your finished order. Compare the first and the last object directly. If the shortest really is shorter than the longest, and each step looked right, your order can be trusted. Try it once with someone beside you, then try it alone.