Respuesta :

9514 1404 393

Answer:

  10%

Step-by-step explanation:

We assume the "sum" being referred to in both cases is the principal amount invested. The simple interest formula tells you ...

  I = Prt . . . . . . interest on P invested at annual rate r for t years

We have ...

  • I = 0.3P
  • t = 3

Filling in these values, we get ...

  0.3P = Pr(3)

  0.1 = r . . . . . . . . divide by 3P

The interest rate is 0.1×100% = 10% per year.