3500÷70= 500×60= 198÷40≈
28×51≈ 320÷40×5=
⑴618÷30
⑵500÷82
⑶783÷37
⑷318÷35
⑤2600÷1600
验算:
35×4 = 23×6= 120×5=
105×8= 7×190= 16×50=
103×98≈ 501×62≈ 79×48≈