Calculating simple interest Practice Test

Jessica deposits $5,000 in a savings account that collects 6% simple interest. How much money will she have accumulated after 5 years?

Grandpa Jack wants to help pay for college for his grandson, Little Jack. Little Jack is currently 8 years old. Grandpa Jack makes a one-time deposit into an account that earns simple interest every year. Grandpa Jack invests $10,000 now and in ten years, that will grow to $15,000. What rate of simple interest did Grandpa Jack receive?