一个长方形操场,长80米,宽60米,现在要扩建这个场地,长增加25米,宽增加15米.扩建后的面积增加了多少平方米?(试着用两种方法计算)
直接写出得数×3= ×16= ×= (+)×4=×+×= += ÷3= 4÷=
= = = == = = == = = == = = =
×1= 52﹣42= 0.75﹣0.5= ×= ÷= 125×0.08=0.5+0.02= ÷= ÷= 0.15×6= 12÷0.3= 0÷=
直接写得数.×16= 12÷= 24×= ×÷=1÷= ÷15= ÷= ×÷×=
直接写得数.10÷= ÷= ×= 55×÷=×2= 1÷= ÷= 0×+=