文档介绍：50 X 50= 810 + 9=
300X6= 25+41=140+7=
20X31 = 90-65=52 X 44〜
74X54 "
41 X 75 〜 40X70= 131+6 ~ 900+ 3=
57 + 29 =
12=
299 + 6〜
500 + 500 =
24X2=
50X7=
33X2=
30X70=
0X37=
800+2=
10X74=
53- 14=
700-8=
50X10=
17+27=
0+47=
70X11 =
840-4=
560+7=
30X40=
2X 14=
440+4=
24X20=
140-2=
93+3=
12X20=
660+6=
24X2=
30X21 =
7X800=
0+ 54=
20X70=
7X700=
23X3=
28X1 =
840+2=
12X30=
20X13=
430X2=
7X80=
1X36=
540+9=
48X 10=
10X19=
31X3=
40X40=
11 X 50=
13X3=
40X 10=
30X30=
34+56=
89 + 3=
28X10=
96+3=
562+ 7勺
20X50=
2X330=
241+2 =
10X36=
50X6=
30-(3-1)=
30X33=
159 + 4 2
24X2-3 =
21X40=
620+2=
0+ 54=
12X10=
6X800=
(23-3) X3=
31X2=
960+3=
13X30=
14X20=
1500-903 =
7X8 1 =
6X90=
1807-800 =
53X10=
20X33=
63+ 3=
60 X 70 =
90X20=
20X13=
4X90=
5X900=
31X20=
60 X 60=
10X33=
22X3=
60X40=
22X0=
60X90=
90X30=
80X70=
39X10=
21X40=
201 X 4=
21X2=
30X20=
0-20=
44X20=
40X90=
6X 60=
12X4=
2X31 =
22X40=
22X30=
33X20=
44 + 20 =
22X4=
40X70=
41 X39〜
30X80=
48+19 =
43X20=
33X10=
70X6=
46 + 37 =
50X90=
4X900=
420-6=
12X40=
2X310=
300-6=
220X3=
20 + 35 =
40X 11 =
22X40=
45 + 35 =
360+9=
90X40=
32X20=
10X34=
200X3=
70X60=
40X90=
41X20=
84X 1 =
90X60=
21X30=
900X6=
490-7=
10X46=
34X20=
20X34=
3X700=
33X30=
300X3=
33X30=
31X20=
80X4=
20X41 =
702X6=
65X0=
6X 600=
84 X