Investment Bank Question

Question

Marsha and Jan both invested money on March​ 1, 2007. Marsha invested ​$8,000 at Bank A where the interest was compounded quarterly. Jan invested $5,000 at Bank B where the interest was compounded continuously. On March​ 1, 2012​, Marsha had a balance of ​$10,638.10 while Jan had a balance of $6,347.17.

What was the interest rate at each​ bank? (Round to the nearest tenth of a​ percent.)

Answer 1

Marsha

10683 = 10000(1 + r/4)⁽⁴⁾⁽⁵⁾

Jacob

6,347.17 = 5000e^5r