7×101 5.5×9.8 82×0.9 0.36×0.25 100-15×4.6 2.04×52 9+5.29

问题描述:

7×101 5.5×9.8 82×0.9 0.36×0.25 100-15×4.6 2.04×52 9+5.29

1.7×101=1.7×(100+1)=170+1.7=171.7
5.5×9.8=5.5×(10-0.2)=55-1.1=53.9
82×0.9=82×(1-0.1)=82-8.2=73.8
0.36×0.25 =0.6×0.6×0.5×0.5=0.3×0.3=0.09
100-15×4.6=100-15×4-15×0.6=100-60-9=31
2.04×52=(2+0.04)×52=104+2.08=106.08
9+5.29 =9+5.3-0.01=14.3-0.01=14.29
432÷48=(480-48)÷48=10-1=9

1.7 × 101 = 1.7 × (100 + 1) = 170 + 1.7 =171.7
5.5 × 9.8 = 5.5 × (10 - 0.2) = 55 - 1.1 = 53.9
82 × 0.9 = 82 × (1 - 0.1) = 82 - 8.2 = 73.8
0.36 × 0.25 = 0.09 × (4 × 0.25) = 0.09 × 1 = 0.09
100-15 × 4.6
2.04 × 52 = (2 + 0.04) × 52 = 104 + 2.08 = 106.8
9+5.29
432 ÷ 48 = (6 × 8 × 9) ÷ (6 × 8) = 9

1.7*101=1.7*(100+1)=170+1.7=171.7
5.5*9.8=5.5*(10-0.2)=55-1.1=53.9
82*0.9=82*(1-0.1)=82-8.2=73.8

题目叙述有问题吧1.7×101 5.5×9.8 82×0.9 0.36×0.25 100??
“0.9 0.36”??

应该1.7×101=1.7×(100+1)=170+1.7=171.75.5×9.8=5.5×(10-0.2)=55-1.1=53.982×0.9=82×(1-0.1)=82-8.2=73.80.36×0.25 =0.6×0.6×0.5×0.5=0.3×0.3=0.09100-15×4.6=100-15×4-15×0.6=...

1.7×101=1.7×(100+1)=1.7×100+1.7×1=1701.7
5.5×9.8 =5.5×(10-0.2)=5.5×10-5.5×0.2=55-1.1=53.9
其余的同上啊 就是一个拆分的关系 尽量拆成整的
0.36×0.25 =(0.6×0.6)×(0.5×0.5)=(0.6×0.5)×(0.6×0.5)=0.3×0.3=0.09

1.7*(100+1)
5.5*(10-0.2)
82*(1-0.1)
0.36÷4
100-(10+5)*4.6
2.04*(50+2)
10+5.29-1
432÷6÷8