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下面各题,能简算的要用简便方法计算.19.8-(9.8+0.3)35.7-2.8×2+1.40.5×(8.55-6.15)÷0.251.25×32×2.55.83×0.9-4.83×0.91÷(8×0.125-0.8)

题目详情
下面各题,能简算的要用简便方法计算.
19.8-(9.8+0.3)35.7-2.8×2+1.40.5×(8.55-6.15)÷0.25
1.25×32×2.55.83×0.9-4.83×0.91÷(8×0.125-0.8)
▼优质解答
答案和解析
①19.8-(9.8+0.3)
=19.8-9.8-0.3
=10-0.3
=9.7

②35.7-2.8×2+1.4
=35.7-5.6+1.4
=30.1+1.4
=31.5

③0.5×(8.55-6.15)÷0.25
=0.5×4×(8.55-6.15)÷0.25×4
=2×2.4÷1
=4.8

④2.5×1.25×32  
=2.5×1.25×4×8
=(2.5×4)×(1.25×8)
=10×10
=100

⑤5.83×0.9-4.83×0.9
=0.9×(5.83-4.83)
=0.9×1
=0.9

⑥1÷(8×0.125-0.8)
=1÷(8×0.125-0.8)
=1÷0.2
=5