Simplify the following text for a Grade 8 native English-speaking person.
Original: These numbers are increased by the daily influx of approximately 300,000 commuters working in the City , with an additional 300,000 cars passing through the square mile a day , along with thousands of tourists .
Simplified: These numbers are increased by the daily influx of approximately 300,000 commuters working in the City , and many tourists . 300,000 cars passing through the square mile a day .