Here are four scores from a school sports day, all jumbled up: 120, 210, 102 and 201. Which score do you think is the lowest? How could we line all four up from lowest to highest?

Look at these three sets of numbers. We order each set by comparing column by column.

• 120, 210, 102
• 305, 350, 35
• 444, 404, 440

Watch where we look first when the hundreds match, and where we go next when the tens match too.

Today we order these three numbers together, dragging each one into a line from smallest to largest. We'll start with 130, 103, 113 — three numbers that look alike, so we'll say each one aloud first. Which number are you sure goes first each time?

Now there are two full sets of four, with the hardest last. The first set is the one you ordered in your copy, 506, 560, 56, 605, so check your line against the board. The two-digit 56 catches people out, so we'll check the digit count first. The second set is 711, 717, 171, 177, where every number uses the same digits and only the columns tell them apart. Which two are easiest to mix up?