4.8x7.8+78x0.52的简便方法?
解: 原式=0.48X78+78X0.52 =78X(0.48+0.52) =78
4.8x7.8+7.8x0.52
4.8x7.8+7.8x0.52
4.8X7.8+7.8X0.52 =7.8X(4.8+0.52) =7.8X5.32 =10X5.32-2X5.32-0.2X5.32 =53.2** =53.2*4 =53.2-12* =41.2* =*
0.8(x+4.8)=5.2急!
X=1.7
7.2x0.2+2.4x1.4的简便算法.
7.2x0.2+2.4x1.4 =2.4x3x0.2+2.4x1.4 =2.4x(0.6+1.4) =2.4x2 =4.8
五年级解方程(1)2.7乘2-1.5x=0(2)13x-6.8x+x=46
(1)2.7乘2-1.5x=0 解:5.4-1.5x=0 1.5x=5.4 x=5.4÷1.5 x=3.6 (2)13x-6.8x+x=46.8 解:(13-6.8+1)x=*.2x=46.8 x=46.8÷7.2 x=6.5 (3)2.6x-6.5+3.5=10 解:2.6x=10+6.5*.6x=13 x=13÷2.6 x=5 (4)2x(x-0.7)=4.8 解:x-0.7=4.8÷2 x