①6.4+3.25+3.6,
=(6.4+3.6)+3.25,
=10+3.25,
=13.25;
②7.26-2.57-3.43,
=7.26-(2.57+3.43),
=7.26-6,
=1.26;
③101×23,
=(100+1)×23,
=100×23+23,
=2323;
④23×134-34×23,
=23×(134-34),
=23×100,
=2300;
⑤99×62+62,
=62×(99+1),
=62×100,
=6200.
①6.4+3.25+3.6,
=(6.4+3.6)+3.25,
=10+3.25,
=13.25;
②7.26-2.57-3.43,
=7.26-(2.57+3.43),
=7.26-6,
=1.26;
③101×23,
=(100+1)×23,
=100×23+23,
=2323;
④23×134-34×23,
=23×(134-34),
=23×100,
=2300;
⑤99×62+62,
=62×(99+1),
=62×100,
=6200.