Multiples of 10
20 x 2
142 + 269
411
746 - 332
414
4 x 100
400
David has 319 baseball cards and he gave 230 to Tom. How many baseball cards does he have now?
89 baseball cards
20 x 8
160
391 + 402
793
853 - 519
334
20 x 100
2000
6 x 7
42
30 x 3
548 + 271
819
517 - 389
128
40 x 100
4000
Annie had 142 marbles at home. Jill gave her 265 more marbles. How many does Annie have now?
407 marbles
50 x 8
400
746 + 286
1,032
793 - 532
261
50 x 100
5000
8 x 9
72
60 x 2
120
659 + 346
1,005
965 - 749
216
30 x 100
3000
9 x 4
36