2005*3/8-0.357*1949+3.75*2.4

2005*3/8-0.357*1949+3.75*2.4
2005*3/8-0.357*1949+3.75*2.4

2005*3/8-0.357*1949+3.75*2.4
2005*3/8-0.357*1949+3.75*2.4
=2005×0.375-0.375×1949+0.375×24
=0.375×（2005-1949+24）
=0.375×80
=30；

2005*3/8-0.375*1949+3.75*2.4
=2005*0.375-0.375*1949+0.375*24
=0.375*(2005-1949+24)
=3/8*80
=30

2005×3/8－0.375×1949＋3.75×2.4
＝2005×3/8－3/8×1949＋3/8×24
＝(2005－1949＋24)×3/8
＝80×3/8
＝30