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能用用简便方法计算的就用简便方法2.8×7.6+1.4×2.8+2.84.5×1.2-3.15÷15[12.8-(7.5+4.5)]×2.50.65+2.7+0.35+7.33.8×0.56+0.56×6.2(10.8-2.7)÷(9.2+8.8)

题目详情
能用用简便方法计算的就用简便方法
2.8×7.6+1.4×2.8+2.8    

4.5×1.2-3.15÷15

[12.8-(7.5+4.5)]×2.5
0.65+2.7+0.35+7.3    3.8×0.56+0.56×6.2    (10.8-2.7)÷(9.2+8.8)
▼优质解答
答案和解析
(1)2.8×7.6+1.4×2.8+2.8
=2.8×(7.6+1.4+1)
=2.8×10
=28

(2)4.5×1.2-3.15÷15
=5.4-0.21
=5.19

(3)[12.8-(7.5+4.5)]×2.5
=[12.8-12]×2.5
=0.8×2.5
=2

(4)0.65+2.7+0.35+7.3
=(0.65+0.35)+(2.7+7.3)
=1+10
=11

(5)3.8×0.56+0.56×6.2
=(3.8+6.2)×0.56
=10×0.56
=5.6

(6)(10.8-2.7)÷(9.2+8.8)
=8.1÷18
=4.5.