如题所述
第1个回答 2020-02-18
99×78+66×33
=99×78+22×(3×33)
=99×78+22×99
=99×(78+22)
=99×100
=9900本回答被网友采纳
=99×78+22×(3×33)
=99×78+22×99
=99×(78+22)
=99×100
=9900本回答被网友采纳
第2个回答 2020-02-18
99X78+66X33
=(66+33)X78+66X33
=66X78+66X33+33X78
=66X111+33X78
=66X(100+11)+33X(100-22)
=6600+3300+66X11-33X22
=9900+66X11-33X2X11
=9900
=(66+33)X78+66X33
=66X78+66X33+33X78
=66X111+33X78
=66X(100+11)+33X(100-22)
=6600+3300+66X11-33X22
=9900+66X11-33X2X11
=9900
第3个回答 2020-02-18
=99×(78+22)
=99×100
=9900
=99×100
=9900