下面的两个算式都是错误的,各移动2根火柴,使它们都变成正确的算式:
脱式计算.(能简算的要写出简算的主要过程)
12×(+
﹣
)920÷40+23×99
×(4.85÷
﹣3.6+6.15×3
)
×[0.75﹣(
+25%)].
(1)1125﹣997(2)12﹣(1
+2
)(3)(
﹣
)×12
(4)4.35+4.25+3.65+3.75 (5)17﹣3
﹣4
(6)22.3﹣2.45﹣5.3﹣4.55
(7)187.7×11﹣187.7(8)998+1246(9)400÷125÷8
(10)1×2
×
(11)34×(2+
)(12)3.4×99+3.4
(13)÷2
+
×
(14)(
+
+
)×72(15)43
×
+57.125×
﹣0.5
(16)4+3.2+5
+6.8(17)25×(37×8)(18)125×8.8
(19)17.15﹣8.47﹣1.53(20)0.125×0.25×32(21)4.25﹣3﹣(2
﹣1
)
(22)2.42÷+4.58×
﹣4÷3.
简便计算:
1000÷32÷0.25÷1.25166×2
×3
×5
÷(3.35×5.625×2.12)
直接写得数.
1﹣+
=1÷
×
=0.5﹣
+0.5﹣
=
1+=(
+
)×24=7÷
×7÷
=
8.1﹣0.9=72÷0.4=1.25×8=
计算下面各题,能简算的要简算.
(1)(+
)×15(2)
×
+
×
(3)
×
×
(4)2.5×97×0.4(5)1.25×97×8(6)1.25×32×2.5×97
(7)0.36×101(8)0.36×98(9)﹣
×
(10)+
×
(11)
+
×
(12)
﹣
×
(13)90×(14)86×
(15)
×
﹣
×
(16)0.36×101﹣0.36(17)0.36×99+0.36(18)×
﹣
.