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There are more than 87,000 flights per day in the United States.
Many of them are nonstop flights across the country. Jupiter
Airlines takes off from Pittsburgh on its way to Los Angeles flying
at the rate of 500 miles per hour. Saturn Airlines leaves Los Angeles
at the same time flying toward Pittsburgh. It is flying at 550 miles
per hour. At one point, they will pass each other but at different
altitudes. It is 2,100 miles from Pittsburgh to Los Angeles. How long
will it take before the planes pass each other? How far will Jupiter
Airlines be from Pittsburgh at that point?