问题 填空题
求值:
919191
393939
+
910910
390390
+
91009100
39003900
=______.
答案

设91=x,39=y,

原式=

10000x+100x+x
10000y+100y+y
+
10000x+10x
10000y+10y
+
1000000x+100x
1000000y+100y

=

x
y
+
x
y
+
x
y
=3×
91
39
=7.

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