Estimation
Estimate the difference.
87 - 28 =
60
Round to the nearest ten.
81
80
Solve using Count On.
341 + 204 =
545
Solve using Count Back.
576 - 342 =
234
Solve using Repeated Addition.
2 x 6 =
12
Estimate the sum.
233 + 498 =
700
Round to the nearest ten.
138
140
Solve using Adjusting.
112 + 98 =
210
Solve using Think Addition.
578 - 196 =
382
Solve using Equal Groups.
5 x 2 =
10
Estimate the sum.
457 + 113 =
600
Round to the nearest hundred.
652
700
Solve using Partial Sums.
543 + 389 =
932
Solve
857 - 324 =
533
Solve using Number Line.
7 x 3 =
21
Estimate the difference.
772 - 431 =
400
Round to the nearest ten.
889
890
Solve using Partial Sums.
477 + 296 =
773
Solve using Count Back.
658 - 562 =
96
Show an Array for
5 groups of 3
15
Estimate the sum.
375 + 289 + 151 =
900
Round to the nearest hundred.
909
900
Solve using Count On.
305 + 244 =
649
Solve
783 - 551 =
232
Solve using Number Line.
7 x 4 =
28