Task# Adding Base Ten Numbers, Part 2

Illustrative MathematicsVaries

This is the second in a set of three tasks generalizing the addition algorithm shown below from whole numbers to all base-ten numbers. In the first set of sums, no regrouping is required. Items (a) through (f) involve addition problems students may have seen in previous grades; then students engage in a mild version of MP8 as this repeated reasoning is extended to decimals beyond the hundredths place. Students may simply use their understanding of the place value system to write sums, or some students may need to draw diagrams akin to Part 1 to support their reasoning.