1.用一块4米长宽1.5米的长方形纸做直角边分别是20厘米和15厘米的三角旗,一共可以做多少面小旗?2.简便计算6.27×3.6+37.8×0.36（0.64+0.32）÷0.64369×0.99+3.6913.5×2.5-0.35×25

1.横向可以做20个20厘米的边。纵向可以做10个15厘米的边，深意一共可以做20*10*2=400个
2. 6.27×3.6+37.8×0.36 = 6.27×3.6+3.78×3.6=（6.27+3.78）*0.36=3.618
（0.64+0.32）÷0.64=0.64÷0.64 + 0.32÷0.64 = 1 +0.5 =1.5
369×0.99+3.69=3.69*99+3.69=3.69*（99+1）=369
13.5×2.5-0.35×25 = 1.35*25-0.35*25=（1.35-0.35）*25=25

1、4m=400cm 1.5m=150cm
400×150÷（20×15÷2）
=60000÷150
=400（面）
2、6.27×3.6+37.8×0.36
=3.6×（6.27+3.78）
=3.6×10.05
=36.018
（0.64+0.32）÷0.64
=0.64÷0.64+0.32÷0.64
=1+0.5
=1.5

369×0.99+3.69
=3.69×99+3.69
=3.69×100
=369
13.5×2.5-0.35×25
=1.35×25-0.35×25
=（1.35-0.35）×25
=25

1.用一块4米长宽1.5米的长方形纸做直角边分别是20厘米和15厘米的三角旗，一共可以做多少面小旗？
4m=400cm 1.5m=150cm(400/20)x(150/15)x2=400(面)
2.简便计算
6.27×3.6+37.8×0.36
=6.27X3.6+3.78X3.6
=36
（0.64+0.32）÷0.64
=1+32/64=1.5
369×0.99+3.69
=369X(0.99+0.01)=369
13.5×2.5-0.35×25
=13.5X2.5-3.5X2.5=25
请采纳!!!!

400/20=20
150/15=15
最多15
6.27*3.6+37.8*0.36
=6.27*3.6+3.78+3.6
=36
（0.64+0.32）/0.64
=0.064
369*0.99+3.69
=369*0.99+369*0.01
=369*2
=783

（1）、4米=400厘米、1.5米=150厘米
面数=400×150÷（20×15÷2）=400（面）
（2）、①6.27×3.6+37.8×0.36
=6.27×3.6+3.78×3.6
=3.6×（6.27+3.78）
=3.6×10.05
=36.18
②（0.64+0.32）÷0.64
=0.64÷0.64+0.32÷0.64
=1.5
③369×0.99+3.69
=3.69×99+3.69×1
=3.69×（99+1）
=3.69×100
=369
④13.5×2.5-0.35×25
=13.5×2.5-3.5×2.5
=2.5×（13.5-3.5）
=2.5×10
=25

1.400×150÷(20×15÷2)=400(面)
2.6.27×3.6+37.8×0.36
=62.7×0.36+37.8×0.36
=(62.7+37.8)×0.36
=100×0.36+0.5×0.36
=36+0.18
=36.18

（0.64+0.32）÷0.64
=0.64÷0.64+0.32÷0.64
=1+0.5
=1.5
369×0.99+3.69
=369×0.99+369×0.01
=369×(0.99+0.01)
=369
13.5×2.5-0.35×25
=13.5×2.5-3.5×2.5
=(13.5-3.5)×2.5
=25
希望对你有帮助