Texas Math Models

Try “number line” or “4.5D”

Whole known, part unknown

whole − part = part

G3

The drive collected 423 cans. 248 came from 3rd grade. How many from 4th?423248?3rd grade4th gradesame bar as card 1, different piece missing248 + ? = 423a missing PART is a subtraction423 − 248 = 1754th grade collected 175cover the ? with your finger: what is left is what you subtract from

How this one works

How

same bar, but now the ? is inside one of the parts.

Best when

you know the total and only one of the parts.

seen one of these on a test? See it on a real question: TEKS 4.5A, multi-step problems with a strip diagram.

The same problem, other ways