A population P is initially 1000. How do you find an exponential model (growth or decay) for the population after t years if the population P is increases by 200% every 6 years?

1 Answer
Jul 5, 2016

#P = 1000 (3^(1/6))^t#

Explanation:

its +ve growth so the basic equation is

#P = P_o e^{kt}# {where P = P(t)}

manipulating....
#(P) /P_o = e^{kt}#

#ln (P /P_o) = kt#

#k = 1/t *ln (P /P_o) #

"the population P is increases by 200% every 6 years"

#k = 1/6 *ln ((P_o(1+2)) /P_o) #

# = 1/6 *ln 3 = ln 3 ^ (1/6) #

so

#P = = 1000 (e^(kt)) = 1000 (e^k)^t= 1000 (e^( ln 3 ^ (1/6)))^t#

# = 1000 (3^(1/6))^t#

test

t = 0, P = 1000
t = 6, P # = 1000 (3^(1/6))^6 = 3000#