10. (3 points) A turtle and a rabbit are racing on a 1000-meter track. The rabbit's speed is 15 times that of the turtle. However, the rabbit took a rest during the race. When it woke up, it found that the turtle had just reached the finish line, and at that moment, the rabbit was still 100 meters away from the finish line. How many meters did the turtle crawl during the rabbit's rest period? $\qquad$ meters.
10. (3 points) A turtle and a rabbit are racing on a 1000-meter track. The rabbit's speed is 15 times that of the turtle. However, the rabbit took a break during the race, and upon waking up, it found that the turtle had just reached the finish line, while the rabbit was still 100 meters away from the finish line. Therefore, the turtle crawled 940 meters during the rabbit's rest.
【Analysis】According to the problem, the rabbit ran a total of $1000-100=900$ (meters). Since the rabbit's speed is 15 times that of the turtle, the turtle ran $900 \div 15=60$ (meters) while the rabbit was running. The turtle actually ran 1000 meters, so it ran $1000-60=940$ (meters) while the rabbit was sleeping, solving the problem.
【Solution】Solution: $1000-(1000-100) \div 15$
$$
\begin{array}{l}
=1000-900 \div 15 \\
=1000-60 \\
=940 \text { (meters); }
\end{array}
$$

Answer: The turtle crawled 940 meters during the rabbit's rest.
The answer is: 940.
【Comment】The solution approach for this problem: First, determine the total distance the rabbit ran, then use the fact that the rabbit's speed is 15 times that of the turtle to find the distance the turtle ran while the rabbit was running, and thus solve the problem.