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脱式计算.(能简算的要简算)78×9.9+7.825×32×1.25(0.18+910)÷912×[(116-23)×3]213÷1839÷627359+4.7+49+0.3.

题目详情
脱式计算.(能简算的要简算)
78×9.9+7.8       25×32×1.25     (0.18+
9
10
)÷9
12×[(
11
6
-
2
3
)×3]
2
13
÷
18
39
÷
6
27
3
5
9
+4.7+
4
9
+0.3.
▼优质解答
答案和解析
(1)78×9.9+7.8  
=7.8×99+7.8×1
=7.8×(99+1)
=7.8×100
=780

(2)25×32×1.25 
=25×4×8×1.25
=(25×4)×(8×1.25)
=100×10
=1000

(3)(0.18+
9
10
)÷9
=(0.18+
9
10
)×
1
9

=0.18×
1
9
+
9
10
×
1
9

=0.02+0.1
=0.12

(4)12×[(
11
6
-
2
3
)×3]
=12×[
11
6
×3-
2
3
×3]
=12×[
11
2
-2]
=12×
11
2
-12×2
=66-24
=42

(5)
2
13
÷
18
39
÷
6
27

=
2
13
×
39
18
×
27
6

=
1
3
×
27
6

=
3
2


(6)3
5
9
+4.7+
4
9
+0.3
=(3
5
9
+
4
9
)+(4.7+0.3)
=4+5
=9