Task# Adding Base Ten Numbers, Part 1

Illustrative MathematicsVaries

This is the first in a set of three tasks generalizing the addition algorithm shown below from whole numbers to all base-ten numbers. The goal of this task is to demonstrate that since digits in the same place represent the same-sized units, we can always add digits in the same place. If they sum to more than ten, the ten units can be bundled together into a unit that goes with the place to the left, which we represent by placing a 1 in the place to the left. The idea in the given diagram (addition and place value with regrouping) should be familiar to students.