一． 口算× 3= 5÷ = ÷ = × ÷ = ÷ ＝ ×（ ＋ ）= × = ÷5= 0÷ = － =二． 脱式计算,能简算的就简算3.2×6+（1.5+2.5）÷1.60.12× 4.8÷0.12×4.8907×99＋90787.5÷12.5÷8三． 解方程0.36×5- 34 x = 35 25 X-13 X=310 70%X + 20%X = 3.65X－3× ＝ 0.36×5- 34 x = 35 12 x- 25%x = 10x―0.8x―6＝1645%x=45
问题描述：
一． 口算
× 3= 5÷ = ÷ = × ÷ = ÷ ＝
×（ ＋ ）= × = ÷5= 0÷ = － =
二． 脱式计算,能简算的就简算
3.2×6+（1.5+2.5）÷1.6
0.12× 4.8÷0.12×4.8
907×99＋907
87.5÷12.5÷8
三． 解方程
0.36×5- 34 x = 35
25 X-13 X=310
70%X + 20%X = 3.6
5X－3× ＝
0.36×5- 34 x = 35
12 x- 25%x = 10
x―0.8x―6＝16
45%x=45
答
1 看不懂
2 19.2+2.5=21.7 0.12×（4.8+4.8）=1.152
907×（100-1)=907×100-907×1=89793
7÷8=8分之7
3 ⑴1.8-34X =35
34X =33.2
X ≈0.98
⑵12X=310 X ≈25.8
⑶ 90%X=3.6
X =4
⑷2X
⑸11.75X=10
X≈0.85
⑺0.2X = 10
X =50
⑻0.45X=45
X=100