Question

0.7×1又9分之4+2又4分之3×（-15）+0.7×9分之5+4分之1×（-15）

Answer 1

0.7×1又9分之4+2又4分之3×（-15）+0.7×9分之5+4分之1×（-15）
=0.7×1又9分之4+0.7×9分之5+4分之1×（-15）+2又4分之3×（-15）
=0.7×(1又9分之4+9分之5)+(4分之1+2又4分之3)×（-15）
=0.7×2+3×(-15)
=1.4-45
=-43.6

Answer 2

=(7/10) * (13/9) -(11/4)*15+(7/10)*(5/9)-(1/4)*15 1，3两项合并，2，4两项合并
=(7/10)*(13/9+5/9)-(11/4+1/4)*15
=(7/10)*2-3*5
=7/5-45
=43又5分之3