5(w - 1 1/10) = - (w - 8 2/5)

Naomi’s parents want to have 50,000, saved for her college education, if they invest 20000 today and earn 7% interest compound annually, about how long will it take them to save 50 thousand

Having a hard time understanding this question (see attachment).

Jonathan puts $400 in a bank account. each year the account earns 6% simple interest. how much interest will be earned in 5 years?