Advanced Functions,Exponential Functions

  • Thread starter ohhnana
  • Start date
  • #1
25
0

Homework Statement


If a bacteria population doubles in 7 days, when was it half of its present population?


Homework Equations


A=A0(1+i)^n



The Attempt at a Solution


i= 100%=1
 

Answers and Replies

  • #2
34,319
5,970

Homework Statement


If a bacteria population doubles in 7 days, when was it half of its present population?


Homework Equations


A=A0(1+i)^n



The Attempt at a Solution


i= 100%=1
If the bacteria population now is 500,000, when was the population 250,000?
 
  • #3
25
0
what ?
 
  • #4
34,319
5,970
What part of my question did you not understand? This problem is not a complicated one, and you don't need a calculator or any formulas to answer the question.
 
  • #5
186
0
Have you ever seen [tex]P = e^{rt}[/tex] before?

Usually, I would recommend exponential growth/decay for bacteria situations.

Furthermore,

...This problem is not a complicated one, and you don't need a calculator or any formulas to answer the question.
"Doubling" and "halving" are very closely related!
 
  • #6
25
0
yea i seen that formula before , so your saying it's impossible to complete the question?
 
  • #7
34,319
5,970
No, I don't think he is. Can you answer my question: If the bacteria population now is 500,000, when was the population 250,000?
 
  • #8
25
0
in your question would it be in 7 days and if so wouldn't it be in 3.5 days
 
  • #9
34,319
5,970
No, you misunderstood. If the bacteria population was 500,000 today, when in the past was the population 250,000?
 
  • #10
HallsofIvy
Science Advisor
Homework Helper
41,833
956
Let's put it a different way- if the population is 250000 today,when will it be 500000? To answer Mark44's question, work backwards from that.
 

Related Threads on Advanced Functions,Exponential Functions

Replies
4
Views
2K
  • Last Post
Replies
9
Views
2K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
3
Views
1K
  • Last Post
Replies
4
Views
848
  • Last Post
Replies
4
Views
3K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
13
Views
3K
  • Last Post
Replies
3
Views
165
Top