Show:
Round to the nearest ten
Round to the nearest hundred
Estimate the sum
Estimate the difference
100
23
20
100
890
900
100

43+26=

40+30=70

100

63-37=

60-40=20

200
57
60
200
147
100
200

90+37=

90+40=130

200

54-22=

50-20=30

300
476
480
300
555
600
300

172+109=

200+100=300

300

145-56=

100-60=40

400
923
920
400
451
500
400

205+406

200+400=600

400

863-256=

900-300= 600

500
178
180
500
555
600
500

769+445=

800+400=1,200

500

738-326=

700-300=400