•如图所示OA:OB:OC:OD=2:2:3:4; 求(S△AOD+S△OBC):(S△ABO+S△ODC)

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•如图所示OA:OB:OC:OD=2:2:3:4;求(S△AOD+S△OBC):(S△ABO+S△ODC)•如图所示OA:OB:OC:OD=2:2:3:4;求(S△AOD+S△

•如图所示OA:OB:OC:OD=2:2:3:4; 求(S△AOD+S△OBC):(S△ABO+S△ODC)
•如图所示OA:OB:OC:OD=2:2:3:4; 求(S△AOD+S△OBC):(S△ABO+S△ODC)

•如图所示OA:OB:OC:OD=2:2:3:4; 求(S△AOD+S△OBC):(S△ABO+S△ODC)
不难发现,对于ΔAOB与ΔAOD来说,由于同一底边的高相等,故SΔAOB/SΔAOD=OB/OD=2/4,对于ΔCOD与ΔAOD来说,由于同一底边的高相等,故SΔCOD/SΔAOD=CO/AO=3/2,对于ΔAOB与ΔBOC来说,由于同一底边的高相等,故SΔAOB/SΔBOC=AO/CO=2/3,所以可以很容易得知,SΔAOB=1/2SΔAOD=2/3SΔBOC,SΔCOD=3/2SΔAOD=3/2 x2SΔAOB=3SΔAOB,所以可以得到(S△AOD+S△OBC):(S△ABO+S△ODC)=(2+3/2)/(1+3)=7/8