Ann can skate 6 miles an hour. Her friend Glenda can skate 8 miles an hour. If they start in the same place and skate in straight lines in opposite directions for 3 hours, how many miles apart do they end up? Let's be accurate as possible.
First find how far Glenda goes in 3 hours by multiplying her speed by the number of hours she travels: 3 hours * 8 miles / hour = 24 miles. Then do the same thing for Ann: 3 hours * 6 miles / hour = 18 miles. Now add the number of miles both people skated to find the total distance between them: 18 miles + 24 miles = 42 miles.
The answer: 42.