1.6/5吨:750千克=6/5*1000千克:750千克=8:5
2.6x-3/10=1/2
6x=1/2+3/10
6x=5/10+3/10
x=(8/10)/6
x=2/15
x-3x/5=3/5*2/9
5x/5-3x/5=6/45
2x/5=6/45
x=(6/45)*(5/2)
x=1/3
(2/5)/(x/4)=7/5
x/4=(2/5)/(7/5)
x/4=2/7
x=2/7*4
x=8/7
3.(1)8x-3/4*2/3=1/2;解得x=1/8
(2)(5/6+1/9)*(5/6-2/3)=17/108
4.(1)(180*2/3)/(2/3)=180
(2)梨树有1200-1200*1/3=800,于是总共有1200+800=2000;
(3)9+9/(1-5/8)=33吨
5.9/5*3/4=27/20
1-7/10=3/10
1/2+3/5=11/10
10/(5/8)=16
28*3/14=6
(1/3)/(5/3)=1/5