Problema Solution

The relative growth rate of a certain bacteria colony is 26%. Suppose there are 6 bacteria initially.

a)Find a function that describes the population of bacteria after t hours.

b) How many bacteria should be expected after 2 days?

a) P(t)=

Answer provided by our tutors

given , initial no. of bacteria = 6

rate of colony = 26

lets first observe some terms of the situation ......

at hr = 0

no. of bacteria = 6 = 6(1.26)0

at hr = 1

no. of bacteria = 6+ 26%of 6 = 6+0.26(6) =6(1.26)1

at hr = 2

no. of bacteria = 6(1.26) + 0.26(6(1.26)) = 6(1.26)(1.26) = 6(1.26)2

at hr = 3

no. of bacteria = 6(1.26)2+0.26(6(1.26)2)) = 6(1.26)2(1.26) = 6(1.26)3

 

a) therefore we can write that,

 after 't' hrs i.e at hr=t

 population,P(t) = 6(1.26)t  which is the required function

 

b) after 2 days = 48 hrs

P(48)=6(1.26)48 = 6(65733.41) = 394400 (approx) => population of bacterias after 2 days

 

C) P(t) = 6(1.26)t