The Half Life of radioactive plutonium 239 is 25,000 yrs. If 16 grams are initially present after 125,000 years?
A=Ao e^kt
A=.5 grams
300
A wine company needs to blend a wine with 5% Alcohol content and a french wine with a 9% Alcohol content to obtain 200-gallons of wine with a 7% alcohol content. How many gallons of each kind of wine must be used?
100 gallons of 5%
100 gallons of 9%
300
ln e^x - ln e^3 = lne^6
x=9
300
6x+2y=7
No Solution
400
log (base 6) (x+5) +log (base 6) X=2
x=4 (x cannot equal -9 because why?)
400
Find the Exponential growth model given the following data:
yr 2000 ->pop was 3.2 million
yr 2050 ->pop will be 12 million
A=Ao e^kt
A=Ao e^.0264t
400
Decay: 1/2 life of Thorium-229 is 7340 years. How long will it take for this substance to decay to 20% of the original amount?
A=Ao e^kt
17,049 years
(this is from notes on 11/14/13 Section 3.5 #4)
400
2x+5y=1
(-2,1)
400
5e^x=23
x=ln(23/5) Exact Answer
x~1.53 Approx Answer
500
log(x+7)-log3=log(7x+1)
x=1/5
500
When will the population reach 15 million?
yr 2000 ->pop was 3.2 million
yr 2050 ->pop will be 12 million
A=Ao e^kt
Year 2059 ->59 years
500
In 2010 the pop in Asia was 4121 million
In 2050 it is projected to be 5231 million
Write an exp. growth model to model the given data.
A=Ao e^.006
(this is from notes on 11/14/13 Section 3.5 #4)