y-5 2y+3 1 y+7 y ----- + -------- + --- = ------ + --- 2 5 3 15 2

(y-5)/2+(2y+3)/5+1/3=(4+7)/15+y/2(*30) 30(y-5)/2+30(2y+3)/5+30*1/3=30(4+7)/15+30(y/2) 15(y-5)+6(2y+3)+10=2(4+7)+15y 15y-45+12y+18+10=8+14+15y 15y+12y-15y=8+14+45-18-10 12y=39 y=39/12 y=3i3/12 y=3i1/4