5/6×1/13+5/9×2/13+5/18×6/13.
问题描述:
×5 6
+1 13
×5 9
+2 13
×5 18
. 6 13
答
×5 6
+1 13
×5 9
+2 13
×5 18
6 13
=
×1 6
+5 13
×2 9
+5 13
×6 18
5 13
=(
+1 6
+2 9
)×6 18
5 13
=
×13 18
5 13
=
5 18