Looking for a Pair That Makes Ten First, Then Adding the Rest

This is not just for paper. Workers group things helpfully all the time. Eggs come in cartons, sodas in packs. Grouping into tens makes counting quick. This is worth learning because ten is the friendliest number in our whole number system.

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. Today you get to learn something useful. Here is a smart trick. When adding three numbers, look for two that make ten and add those first.

In 7 plus 3 plus 5, seven and three make ten, and ten plus five is fifteen. Your mind handles ten easily, so making ten first turns a hard problem into an easy one. Scan the three numbers before you start. Finding the friendly pair takes one second and saves you many.

Try this one. In 5 plus 5 plus 7, the fives make ten and ten plus seven is seventeen. Scan first, group second, count last. That order takes one extra second at the start and saves a great deal of counting at the end. Go slowly the first time and faster the fifth time.