Final answer:
To find the miles per hour, divide the total distance by the total time. To find the miles driven in a certain number of hours, multiply the miles per hour by the number of hours.
Step-by-step explanation:
To find the number of miles you can drive per hour, you can divide the total distance by the total time. In this case, you can drive 420 miles in 6 hours, so the number of miles per hour is 420 divided by 6, which is 70 miles per hour.
To find the number of miles you can drive in 20 hours, you can multiply the number of miles per hour (70) by the total number of hours (20). So, you would get 70 times 20, which is 1400 miles.
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