用简便方法计算(要写出简算过程)①475-198②0.7+3.9+4.3+6.1③( 1 3 +

2025-04-07 02:05:33
推荐回答(1个)
回答1:

①475-198,
=475-(200-2),
=475-200+2,
=275+2,
=277;

②0.7+3.9+4.3+6.1,
=(0.7+4.3)+(3.9+6.1),
=5+10,
=15;

③(
1
3
+
2
5
)×15,
=
1
3
×15+
2
5
×15,
=5+6,
=11.