1/4+2x=1/25x-5/6=5/122/3x-3/5x=1x+7/9x=4/320x-100(250-x)=440

1.2x=1/2-1/4
x=1/4*1/2
x=1/8
2.5x=5/12+5/6
x=15/12*1/5
x=1/4
3.(2/3-3/5)x=1
x=1*15
x=15
4.(1+7/9)x=4/3
x=4/3*9/16
x=3/4
5.20x-25000+100x=4400
(20+100)x=4400+25000
x=29400/120
x=245