Chase has a savings account that yields 3% a year and is not compounded. If he makes $480 in interest after 4 years, how much money did he invest initially? (I need help with this)

Find the balance at the end of 4 years if 1000 is deposited at the rate of

What is the product? a-3/15a × 5/a-3

Me with this assignment ! i only partially understand, so explain. also it's a work sample. at the championship bike race, steve and paula were fighting for first place. steve was 175 feet ahead of paula and had only 300 feet left to go. he was very tired and was going only 9 feet per second. paula was desperate to catch up and was going 15 feet per second. who won the bike race and by how far did she/he win?