Vocabulary
The answer to a subtraction equation
Difference
8-5
3
Which neighbor do we look at when we are deciding which way to round?
Our RIGHT neighbor
23+41
64
84 - 23
61
Rearranging groups of 10 to a different place value
Regroup
15 + 9
24
Round 24 to closest 10
20
78 + 11
89
63 - 35
28
A reasonable guess that is close to the exact answer
Estimate
12 + 8
20
Round 476 to the closest 100
500
327 + 264
591
239 - 127
112
Numbers that are close to the original value and make a problem easier to solve
Compatible Numbers
Skip count by 10s from 0-100
10, 20, 30, 40, 50, 60, 70, 80, 90, 100
Round 338 to the closest 10
340
629 + 267
896
536 - 257
279
A plan or way of solving a problem
Strategy
If 3 + 1 = 4, then ___ - ___ = 3
4,1
Round 2,578 to the closest hundred
2,600
793 + 215
1,008
618 - 523
95