∵an为等差数列
a1,a3,a9成等比数列
∴a1(a1+8d)=(a1+2d)^2
a1^2+8d*a1=a1^2+4d*a1+4d^2
d≠0
∴d=a1
a1+a3+a9/a2+a4+a10=(a1+a1+2d+a1+8d)/(a1+d+a1+3d+a1+9d)
=13a1/16a1=13/16