Question

如果A=12356.79×975.431：B=123.5678×97543.2，那么A（　�。〣．

A．大于

B．小于

C．等于

D．無(wú)法確定

Answer 1

分析：通過(guò)觀察，A和B兩個(gè)算式中的數(shù)字很接近，于是可通過(guò)變化，把A變?yōu)锳=1235679×9.75431=（1235678+1）×9.75431=1235678×9.75431+9.75431，把B變?yōu)锽=123.5678×97543.2=1235678×9.75432=1235678×（9.75431+0.00001）=1235678×9.75431+12.35678，則A-B=1235678×9.75431+9.75431-（1235678×9.75431+12.35678）=9.75431-12.35678＜0．據(jù)此解答．

解答：解：A=1235679×9.75431=（1235678+1）×9.75431=1235678×9.75431+9.75431，
B=123.5678×97543.2=1235678×9.75432=1235678×（9.75431+0.00001）=1235678×9.75431+12.35678，
則A-B=1235678×9.75431+9.75431-（1235678×9.75431+12.35678）=9.75431-12.35678＜0．
即A＜B．
故選B．

點(diǎn)評(píng)：完成此題，應(yīng)注意分析式中數(shù)據(jù)，通過(guò)轉(zhuǎn)化，靈活解答．