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David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?

The equatorial radius of earth is approximately 6 × 10^3 km, while the equatorial radius of saturn is approximately 6 × 10^4 km. which of the following is true? a. the equatorial radius of saturn is approximately one hundred times that of earth. b. the equatorial radius of saturn is approximately ten times that of earth. c. the equatorial radius of earth is approximately one hundred times that of saturn. d. the equatorial radius of earth is approximately ten times that of saturn.

Find two numbers if their ratio is 4: 7 and their difference is 123.