计算下面各题(能简便计算的要用简便方法计算) 456-199 0.25×5.7×4 252÷24-0.4×6 (3.8-1.8÷2

2025-02-24 19:18:11
推荐回答(1个)
回答1:

(1)456-199,
=456-200+1,
=256+1,
=257;

(2)0.25×5.7×4,
=0.25×4×5.7,
=1×5.7,
=5.7;

(3)252÷24-0.4×6,
=10.5-2.4,
=8.1;

(4)(3.8-1.8÷2)×
1
2

=(3.8-0.9)×
1
2

=2.9×
1
2

=1.45;

(5)(8+
4
9
)÷4,
=(8+
4
9
)×
1
4

=8×
1
4
+
4
9
×
1
4

=2+
1
9

=2
1
9


(6)4.4-
1
5
+1.6-
4
5

=(4.4+1.6)-(
1
5
+
4
5
),
=6-1,
=5.