a/ x/5+1/2=6/10=> 2x/10+5/10=6/10=>2x+5=6=>2x=1=>x=1/2
b/(x+1/8):2/3=9/4=> (x+1/8).3/2=9/4=> 3x/2+3/16=9/4=>24x/16+3/16=36/16=>24x+3=36=>x=11/8
c/x/3-1/4=-5/63-3/4=>x/3+1/2=-5/63=>x/3=73/126=> x=(-73.3)/126=-73/42
d(x+1/8):2/3=3-3/4=>(x+1/8).3/2=9/4=>3x/2+3/16=9/4=>24x/16+3/16=36/16=> 24x+3=36=>11/8