Exponential Growth and Decay -- Quiz

Problem 1. 50 micrograms of radioactive iodine is injected into a patient's bloodstream at time t=0. The amount R(t) left after t days is given by the formula

[Maple Math] .

(a) How much iodine, in micrograms, is going to be left after 3 days?

(A) 20.51 (B) 64.19 (C) 38.56 (D) 27.98

(b) Find the half-life of the iodine, in days.

(A) 11.5 (B) 6.25 (C) 8.00 (D) 12.3

Problem 2. A bank offers 5% annual percentage rate compounded continuously . That means that if your initial deposit is [Maple Math] , the balance on your account after t years is

[Maple Math] .

How many years will it take for your money to double?

(A) 13.86 (B) 1.38 (C) 25.89 (D) 40.00

MTH 111 Quizzes, B. Kaskosz and L. Pakula, 2001.