第1个回答 2022-10-06
①28×25,
=7×(4×25),
=7×100,
=700;
②101×72,
=(100+1)×72,
=100×72+72×1,
=7200+72,
=7272;
③49.62十27.17-19.62,
=49.62-19.62+27.17,
=30+27.17,
=57.17;
④350÷14,
=350÷7÷2,
=50÷2,
=25;
⑤24×19-24×9,
=24×(19-9),
=24×10,
=240;
⑥49×99+49,
=49×(99+1),
=49×100,
=4900.