213×456÷687÷456×687÷213的簡便計算 清楚點
213×456÷687÷456×687÷213
=(213×456÷687)÷456×687÷213
=(213÷687)×687÷213
= 213÷213
=1
15.83-(4.19-2.83)簡便計算怎麼計算
=15.83-2.83+4.19
=13+4.19
=17.19
9又3/4—15/19—2/19*2簡便運算
=9又3/4-15/19-2*2/19 =9又3/4-15/19-4/19 =9又3/4-(15/19+4/19)=9又3/4-1 =8又3/4
-19又9分之8乘3的簡便運算
-19又9分之8×3
=[-20+(1/9)]×3
=-20×3+(1/9)×3
=-60+(1/3)
=-59又3分之2