Advanced Functions,Exponential Functions

[ohhnana]

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

 

[Mark44]

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?

 

[ohhnana]

what ?

 

[Mark44]

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.

 

[The Chaz]

Have you ever seen $$P = e^{rt}$$ 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!

 

[ohhnana]

yea i seen that formula before , so your saying it's impossible to complete the question?

 

[Mark44]

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?

 

[ohhnana]

in your question would it be in 7 days and if so wouldn't it be in 3.5 days

 

[Mark44]

No, you misunderstood. If the bacteria population was 500,000 today, when in the past was the population 250,000?

 

[HallsofIvy]

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.