Texas Math Models

Try “number line” or “4.5D”

Vertical number line

4,367 + 2,258 = 6,625 Grade 4

the same number rounds UP to one place and DOWN to another to the nearest hundredto the nearest thousand 4,4004,300 4,350 · halfway 4,367 past halfway → 4,400 5,0004,000 4,500 · halfway 4,367 not yet halfway → 4,000

How this one works

How

mark the number between two hundreds, or two thousands, and see which is nearer.

Best when

you are deciding which place to round to.

The same problem, other ways