Explain why percents are rational numbers

Really need on these. i have no idea what to do

The marriott family bought a new apartment three years ago for $65,000. the apartment is now worth $86,515. assuming a steady rate of growth, what was the yearly rate of appreciation? what is the percent of the yearly rate of appreciation?

Which shows one way to determine the factors of 4x3 + x2 – 8x – 2 by grouping?