Adding
45+23
60-30
30
56
60
123
100
Estimate to the nearest tens to get the sum
56+32=
60+30=90
60+30
90
85-23
62
82
80
256
300
Estimate to the nearest tens to get the sum
155+120
160+120=180
123+162
285
250-63
187
123
120
563
600
Estimate to the nearest hundred to get the sum
123+321
100+300=400
45+23+65
133
147-123
24
456
460
925
900
Estimate to the nearest hundred to get the sum
256+412
300+400=700
123+45+23
191
423-321
102
655
660
985
1000
Estimate to get the sum
231+485=
200+500=700
OR
230+490=720