Sam opened a money-market account that pays 2% simple interest. He started the account with $7,000 and made no further deposits. When he closed the account, he had earned $280 in interest. How long did he keep his account open?

Answer 1

since i = Prt, solve this for t:
7000*0.02 t = 280

or, consider that 2% of $7000 is $140 interest each year
so ...