algebra  exponentials
posted by Nilan .
My question is how do I know that
N increases by a factor of 2.9 each day. (see below)
Let N(t) be number of bacteria after t days. N(t) = Pa^t for some constants P and a. N(2) = 5400 and N(6)=382,000.
a)before working problem, estimate value of N(5).
b) write down 2 equations for P and a, one when t=2 and one when t=6, and use these two equations to compute a and P. Round to three significant digits.
algebra  please help  drwls, Sunday, November 6, 2011 at 6:41am
(a) N increases by a factor of 2.9 each day. Divide 382,000 by 2.9 for N(5)
(b) 382,000 P*a^6
5400 = P*a^2
70.74  a^4
a = (70.74)^(1/4) = ___
Once you have a, solve for P.

algebra  exponentials 
Steve
Because, as it shows above a = (70.74)^(1/4)= 2.9
and P*a^n multiples by a each day.
Respond to this Question
Similar Questions

algebra  please help
Let N(t) be number of bacteria after t days. N(t) = Pa^t for some constants P and a. N(2) = 5400 and N(6)=382,000. a)before working problem, estimate value of N(5). b) write down 2 equations for P and a, one when t=2 and one when t=6, … 
Math
Let N(t) be the number of bacteria after t days. Then N(t) = Pa^t for some constants P and a. Measurements indicate that N(4) = 5600 and N(8) = 362, 000. a. Before working the problem, estimate the value of N(7), the number of bacteria … 
math
A type of bacteria doubles in number every 12 hours. After 2 days, there are 48 bacteria. How many bacteria were there at the beginning of the first day. 
math
A type of bacteria doubles in number every 12 hours. After 2 days, there are 48 bacteria. How many bacteria were there at the beginning of the first day. I know the answer is 3, but want to know how it arrived at the number "3" 
PreCalc/Trig...
is this the correct formula for me to solve this? 
College Algebra
The number of bacteria in a certain culture increased from 500 to 1000 between 7:00 A.M. and 9:00 A.M. Assuming growth is exponential, the number f(t) of bacteria t hours after 7:00 A.M. is given by f(t) = 500(2)^t/2. (a) Estimate … 
Algebra
(I skipped the lengthy work problem background as it is irrelevant) The number of bacteria needed to break down an oil spill is 1000000 per millitre of oil. The bacteria double in number every two days.The starting concentration of … 
Steve  Stat
A Bacteria has a doubling period of 8 days. If there are 2250 bacteria present now, how many will there be in 33 days? 
Math
There are 3000 bacteria in a day, if the number of bacteria double per 2 days , how many bacteria can we expect to have in 15 days? 
Algebra 1
I am having trouble with a few questions....Wondering if you could help...My answers have the *** by them..... 1. A lab is growing bacteria in a culture dish. The amount of bacteria in the dish doubles every 3 hours. Initially, there …