编写数学动画，现在给你一道公务员招考的数学题，请你给出详细的解答过程，因为你面对的是小学生群体，所以你要尽可能的详细，动画要生动，动画中图形和文字不要重叠。最后对大家的称呼是“同学们”，而不是“小朋友们”。 考题： 张某8:00开车从A地出发，在A、B两地之间往返行驶。8:30第一次到达A、B之间的C点时加速30%继续行驶，并于9:00第二次到达C点。问AC距离是BC距离的多少倍？

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Uncle Zhang starts his car journey at 8:00 AM from point A. He drives at his normal speed between points A and B. At 8:30, he reaches point C for the first time. From 8:00 to 8:30, he took 30 minutes. So the distance AC equals normal speed times 30 minutes. Let's remember this important fact! At point C, Uncle Zhang decides to speed up! He increases his speed by 30 percent. What does this mean? If his original speed was 1 unit, now it becomes 1 plus 0.3, which equals 1.3 times his normal speed. From now on, Uncle Zhang will continue driving with this new faster speed! Uncle Zhang uses his new speed to drive from C to B, then turns around and drives back to C. From 8:30 when he sped up at C, to 9:00 when he returned to C again, he took exactly 30 minutes total. Since the distance from C to B equals the distance from B to C, and he used the same speed throughout, each segment took 15 minutes. So BC distance equals new speed times 15 minutes! Now let's compare AC and BC distances. We know that AC distance equals normal speed times 30 minutes. BC distance equals new speed times 15 minutes. Since new speed is normal speed times 1.3, we can rewrite BC as normal speed times 1.3 times 15 minutes. Now we need to calculate how many times AC is compared to BC! Let's calculate step by step! AC divided by BC equals normal speed times 30, divided by normal speed times 1.3 times 15. We can cancel out normal speed, leaving 30 divided by 19.5. Converting to whole numbers: 300 divided by 195. Dividing both by 5: 60 divided by 39. Dividing both by 3: 20 divided by 13. So AC distance is BC distance times 20 over 13! Students, you've successfully solved this math problem!