Math College Work

Question

A retired couple invested $6000 in bonds. At the end of one year, they received an interest payment of $390. What was the simple interest rate of the bonds?

Answer 1

A = A₀(1 + rt), so r = (A/A₀ - 1)/t = [(6000 + 390)/6000 - 1]/1 = 0.065 = 6.5% per year