11. (6 points) A car rally has two equal-distance courses. The first course starts on a flat road, 26 kilometers from the midpoint it begins to climb; 4 kilometers after passing the midpoint, it is all downhill; The second course also starts on a flat road, 4 kilometers from the midpoint it begins to descend, 26 kilometers after passing the midpoint, it is all uphill. It is known that a certain race car used the same amount of time on these two courses; the speed at the start of the second course is $\frac{5}{6}$ of the speed at the start of the first course; and when encountering an uphill, the speed decreases by $25 \%$, and when encountering a downhill, the speed increases by $25 \%$. Therefore, the distance of each course is $\qquad$ kilometers.
【Answer】Solution: $\left(30 \div 4.5+22 \div \frac{45}{8}-30 \div \frac{25}{4}-22 \div 5\right) \div\left(\frac{16}{75}+\frac{1}{5}-\frac{1}{6}-\frac{8}{45}\right)=20$ (km); Distance of each stage: $(20+26) \times 2=92$ (km); Therefore, the answer is 92.