homework!!(fast)

1. 3.6 x 2.9 + 0.36 x 71
=0.36 x29+ 0.36 x 71
=0.36 x ( 29+ 71 )
=36

2. 5.1 x 4.9 + 4.9 x 4.9
=4.9 x (5.1+ 4.9+ 0)
=4.9 x 10
=49



3. 2 x 4.5 x 64 + 128 x 5.5
=128x 4.5 + 128 x 5.5
=128 x ( 4.5 + 5.5 )
=1280

2007-10-07 15:11:14 補充：
1. 3.6 x 2.9 + 0.36 x 71=0.36 x29+ 0.36 x 71=0.36 x ( 29+ 71 )=36要先把3.6變成0.36所以3.6變成0.36....2.9就變成29再把0.36弄出來變成0.36 x ( 29+ 71 )29+ 71=100,,,把0.36 x 100 所以=36

2007-10-07 15:11:34 補充：
2. 5.1 x 4.9 + 4.9 x 4.9=4.9 x (5.1+ 4.9+ 0)=4.9 x 10=49一樣把4.9弄出求(4.9) x (5.1 x 4.9)/4.9 + (4.9 x 4.9)/4.9=4.9 x (5.1+ 4.9+ 0) (4.9 x 4.9)/4.9記住小心D一樣把5.1同 4.9+一起=104.9 x 10=49

2007-10-07 15:11:45 補充：
3. 2 x 4.5 x 64 + 128 x 5.5=128x 4.5 + 128 x 5.5=128 x ( 4.5 + 5.5 )=1280 仲易把 64同2 x起把128弄出來再把4.5同5.5加在一起再 x 128=答案1280 lo~~~

1. 3.6 x 2.9 + 0.36 x 71
=0.36 x 29 + 0.36 x 71
=0.36 x ( 29 + 71 )
=36

2. 5.1 x 4.9 + 4.9 x 4.9
=4.9 x ( 5.1 + 4.9 )
=4.9 x 10
= 49

3. 2 x 4.5 x 64 + 128 x 5.5
=128 x 4.5 + 128 x 5.5
=128 x ( 4.5 + 5.5 )
=1280