简算(8/15+9/20*2/3)÷1/12 (0.4+2/3)/(5/6-0.75)*0.5 方程 1/4x+3/4x=1/3 7/16:x =7/8:32/9

问题描述:

简算(8/15+9/20*2/3)÷1/12 (0.4+2/3)/(5/6-0.75)*0.5 方程 1/4x+3/4x=1/3 7/16:x =7/8:32/9

(8/15+9/20*2/3)÷1/12
=(8/15+3/10)×12
=8/15×12+3/10×12
=6.4+3.6
=10
(0.4+2/3)/(5/6-0.75)*0.5
=16/15*0.5/(1/12)
=8/15×12
=6.4
1/4x+3/4x=1/3
x=1/3
7/16:x =7/8:32/9
7/8x=7/16×32/9
7/8x=14/9
x=16/9