Find an equation of F

Question

Suppose that a rumor is spreading. Assume that 30 people have heard the rumor as of today and that each day the total number of people who have heard the rumor triples. Let f(t) be the total number of people who have heard the rumor at t days since today.

Answer 1

f(t) = 30*3^t = (10*3)*3^t = 10*3^t+1

 

f(0) = 10*3¹ = 30            

f(1) = 10*3² = 90                  After 1 day

f(2) = 10*3³ = 270                After 2 days

...

f(7) = 10*3⁸ = 65,610            After a week

 

Rumors really do spread fast!