考點(diǎn):估計(jì)與估算;比較大小.
分析:由題意可知:1234÷3121<商<1234÷3120,進(jìn)而進(jìn)行解答即可;
解答:解:1234÷3121<商<1234÷3120,
1234÷3121≈0.3954,
1234÷3120≈0.3955,
所以商的前三位是0.395,計(jì)算結(jié)果的小數(shù)點(diǎn)后的前三位分別是3、9、5;
故答案為:3、9、5.
點(diǎn)評(píng):解答此題應(yīng)結(jié)合題意,根據(jù)數(shù)進(jìn)行估算(確定范圍),進(jìn)而通過解答得出結(jié)論.