11.75- 1.7=
3.6×0.25×4=
÷=
- =
0.64÷0.08=
27×=
42 :="x" :
求未知数X x-x=
(2.4×1.5-1.5)÷0.7
(3.2+3.2+3.2+3.2) ×2.5
+-
3600÷45×90
×(+0.8÷)
(+)×(1-)
45÷×-1