计算下面各题,能用简便方法算的要简算.24.56-14-4.56-4.75 4.2×5.43+4.57×4.2

2025-05-20 15:04:30
推荐回答(1个)
回答1:

(1)24.56-

1
4
-4.56-4.75,
=24.56-0.25-4.56-4.75,
=(24.56-4.56)-(0.25+4.75),
=20-5,
=15;

(2)4.2×5.43+4.57×4.2,
=4.2×(5.43+4.57),
=4.2×10,
=42;

(3)6035-450÷30×15,
=6035-225,
=6000+35-(200+25),
=(6000-200)+(35-25),
=5800+10,
=5810;

(4)
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