4. Given an arithmetic sequence $\left\{a_{n}\right\}$ with a common difference of $d \neq 0$, and $a_{1} 、 a_{3} 、 a_{9}$ form a geometric sequence, the value of $\frac{a_{1}+a_{3}+a_{9}}{a_{2}+a_{4}+a_{10}}$ is $\qquad$ .