1) You have been given values for A, r, n, and t, and have been asked to find the value of P. So plug the given values into the compound-interest formula they gave you, and solve for the value of P.

2) You have been given values for P and r, been told how to find the value for A, and been asked for the value of t. So plug the given values into the continuous-compounding formula they gave you, and solve for the value of t.

If you get stuck, please reply showing your work so far. Thank you!