Question

简便计算。4.4×0.25，0.26×5.5+2.6×0.45，19.9×0.67，0.8×32.

简便计算。4.4×0.25，0.26×5.5+2.6×0.45，19.9×0.67，0.8×32.4×12.5

Answer 1

解：4.4*0.25=4.4/4=1.1； 0.26*（5.5+4.5）=2.6；（20-0.1）*0.67=13.4-0.067=13.333
0.8*32=（1-0.2）*32=32-6.4=25.6；0.8×32.4×12.5=8*10/8*32.4=324

Answer 2

4.4*0.25的简便计算
=(4+0.4)*0.25
=4*0.25+0.4*0.25
=1+0.1
=1.1

0.26×5.5+2.6×0.45
＝2.6×0.55＋2.6×0.45
＝2.6×（0.55＋0.45）
＝2.6×1
2.6

19.9×0.67

=0.67x(20-0.1)
=0.67x20-0.67x0.1
=13.4-0.067
=13.333

=0.8*12.5*32.4
=10*32.4
=324

Answer 3

4.4×0.25，
=1.1*（4*0.25）
=1.1*1
=1.1
0.26×5.5+2.6×0.45，
=0.26*（5.5+4.5）
=0.26*10
=2.6
19.9×0.67，
=（20-0.1）*0.67
=20*0.67-0.1*0.67
=13.4-0.067
=13.333
0.8×32.4×12.5

=0.8*12.5*32.4
=10*32.4
=324

Answer 4

4.4×0.25
=4.4X1/4
=1.1
0.26×5.5+2.6×0.45
=0.26x（5.5+4.5）
=2.6
19.9×0.67
=20x0.67-0.67x0.1
=13.4-0.067
=13.333
0.8×32.4×12.5
=0.8x12.5x32.4
=10x32.4
=324

Answer 5