Mandy C 9) had 342 visitors to her website in December. In January 464 people visited. What was her percent of increase, to the nearest percent? Tiffany E 10.) is rich. She decides to take $900 and invest part of it at 12% and the rest at 9%. If her total return was $96, how much did she Invest at each rate? Erick D. 11.) is 75 years old and just about ready to retire from his job as head bagger at the local Giant Eagle. Over the years he has accumulated a small fortune. Erick D. He plans to live off his interest for the rest of his life. has $3,000 more invested at 8% than he has invested at 10%. If both investments are earning the same amount of interest, how much money is invested at each rate