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脱式计算(能简算的要简算)①2009×97.75+4018×1.125②4.02×8.1×35÷(0.6×0.81)③9999×8888÷6666④3.6×199425+2006.9×625⑤(1+0.93+0.34)×(0.93+0.34+0.65)-(1+0.93+0.34+0.65)×(0.93+0.34)

题目详情
脱式计算(能简算的要简算)
①2009×97.75+4018×1.125           
4.02×8.1×
3
5
÷(0.6×0.81)
③9999×8888÷6666                  
3.6×1994
2
5
+2006.9×6
2
5

⑤(1+0.93+0.34)×(0.93+0.34+0.65)-(1+0.93+0.34+0.65)×(0.93+0.34)
0.
3
+0.1
1
+0.1
2
+0.1
3
+0.1
4
+0.1
5
▼优质解答
答案和解析
①2009×97.75+4018×1.125,
=2009×97.75+2009×2×1.125,
=2009×(97.75+2.25),
=2009×100,
=200900;

②4.02×8.1×
3
5
÷(0.6×0.81),
=4.02×8.1×0.6÷0.6÷0.81,
=4.02×(8.1÷0.81)×(0.6÷0.6),
=4.02×10×1,
=40.2;

③9999×8888÷6666,
=9999×8×1111÷6666,
=9999×8×(1111÷6666),
=9999×8×
1
6

=13332;

3.6×1994
2
5
+2006.9×6
2
5

=3.6×1994.4+2006.9×6.4,
=3.6×(2000-5.6)+(2000+6.9)×6.4,
=(3.6+6.4)×2000-3.6×5.6+6.9×6.4,
=10×2000+6.9×6.4-3.6×5.6,
=20000+0.3×23×0.8×8-0.3×12×0.8×7,
=20000+0.3×0.8×(23×8-12×7),
=20000+0.24×(184-84),
=20000+24,
=20024;

⑤设1+0.93+0.34=a,1+0.93+0.34+0.65=b,
(1+0.93+0.34)×(0.93+0.34+0.65)-(1+0.93+0.34+0.65)×(0.93+0.34),
=a×(b-1)-b×(a-1),
=ab-a-ab+b,
=b-a,
=(1+0.93+0.34+0.65)-(1+0.93+0.34),
=0.65;

0.
3
+0.1
1
+0.1
2
+0.1
3
+0.1
4
+0.1
5

=
30
90
+
10
90
+
11
90
+
12
90
+
13
90
+
14
90

=1.