## Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)

We can find Alan's driving time. $t = \frac{d}{v} = \frac{400~mi}{50~mph}$ $t = 8 ~hours$ Since Alan leaves at 8:00 am, Alan arrives at 4:00 pm. We can find Beth's driving time. $t = \frac{d}{v} = \frac{400~mi}{60~mph}$ $t = 6.67 ~hours$ $t = 6 ~hours~and~40~minutes$ Since Beth leaves at 9:00 am, Beth arrives at 3:40 pm. (a) Beth gets to San Francisco first. (b) Beth has to wait for 20 minutes for Alan to arrive.