计算下面各题,能用简便方法的要用简便方法.
来源:学生作业帮 编辑:大师作文网作业帮 分类:数学作业 时间:2024/11/10 22:10:36
(1)
4 11 × 1 7 ÷ 4 7 , = 4 11 × 1 7 × 7 4 , = 4 11 ×( 1 7 × 7 4 ), = 4 11 × 1 4 , = 1 11 ; (2) 11 21 × 1 8 + 10 21 ÷8, = 11 21 × 1 8 + 10 21 × 1 8 , =( 11 21 + 10 21 )× 1 8 , =1× 1 8 , = 1 8 ; (3)(15-15× 4 5 )× 7 24 , =(15-12)× 7 24 , =3× 7 24 , = 7 8 ; (4)[ 4 5 -0÷( 1 3 + 2 5 )]× 5 8 , =[ 4 5 -0]× 5 8 , = 4 5 × 5 8 , = 1 2 ; (5)(34+ 34 47 )÷17, =(34+ 34 47 )× 1 17 , =34× 1 17 + 34 47 × 1 17 , =2+ 2 47 , =2 2 47 ; (6)( 5 6 + 2 9 )× 4 5 ÷ 19 20 , = 19 18 × 4 5 × 20 19 , = 19 18 × 20 19 × 4 5 , = 10 9 × 4 5 , = 8 9 . |