第42页

信息发布者:
85
b
+
a
b
3
25
17
+
b
a
+
25
a
a
+
x
C
A
C
257
5
90
930
355
960
30
76500
=165+300-1 =465-1 =464
=47×(9+1) =47×10 =470
=630÷(18×5) =630÷90 =7