If you save one penny on the first day of january, two pennies on the second day of january, three pennies on the third day of january, and continue with this pattern for a whole year, how much will you have saved by december 31?

Apassenger train and a freight train leave san jose at 3pm, traveling in the same direction. the passenger train is going three times as fast as the freight train. at 6pm they are 240 miles apart. how fast is each travelling? explain your answer and show your