Applications of Exponential Growth and Decay Selena Evora

Essential Question How is the exponential growth and decay applied in variety of occupations such as medicine, finance, and paleontology?

Topics Number One: Illegal Marijuana use Number Two: Bank of America interest rates

Background to Marijuana Marijuana is a greenish-gray mixture of dried and shredded leaves, stems, seeds, and flowers from a plant called Cannabis sativa. People who smoke weed roll it up in papers or joints. Marijuana is the most commonly used illicit drug in the US. The drug affects the nerve system and targets a nerve called cannabinoid receptors. Cannabinoid receptors affect the part of the brain that controls the influence of pleasure, memory, thinking, concentration, movement, coordination, sensory, increased anxiety, heart rate and time perception. Most teens use marijuana are in 8th, 10th, and 12th graders. with 6.1% of the teenage population are smokers. Marijuana also has medicinal uses and helps treat glaucoma and cancer patients.

Questions Part A: How long will it take for Marijuana to leave your body? Part B: How many hours will it take for 10% of the Marijuana to leave?

Equation Part A: half life= 20 hours usual blunt=.5 grams y=ae^-kt.5=e^-k20 ln.5=lne^-20k =-20k -20 k=.0346 Part B: half life=.0346 amount:.10 y=ae^-kt.10=e^.0346t log.10=loge.0346t 1=-.0346t.0346 t=28.90

Answers Part A: The constant in the exponential equation is k =.0346 Part B: It takes almost 29 hours for 10% of the Marijuana to leave your system.

Graph for Part A

Background for Bank of America James Madison was the director of the bank. First opened July 5, 1784 The current interest rate for a savings account at Bank of America is.05% for a savings account that holds under $1, years ago in,2003, was 1.90% There was an increase of 1.85% interest in the past 10 years Interest is a way that the account can accumulate more money.

Questions Part A: If the interest rate is.05%, how long will it take my money to reach $1,000.00? Part B: After 10 years, how much money will I have in my savings account?

Equations Part A: interest rate:.05% initial amount: $ end amount: $1, y=a(r+1)^t 1000=600( )^t =1.0005^t ln1.16=ln1.0005^t ln t= Part B: interest rate:.05% initial amount: $ t=10 years y=a(1+r)^t y=600( )^10 y=600(1.0005)^10 $603.00=y

Answers Part A: After 5,546 years your money will have increased by $ Part B: After 10 years you will only have a $3.00 increase in your savings account. I find these numbers outrageous because I have a BoA account and I realized my money is not going to increase any time soon.

Table Part A 1000∞ 2000∞ 3000∞ 4000∞ 5000∞ 6000∞ 7000∞ 8000∞ 9000∞ 10000∞

Works Cited heritage.html#fbid=UMqyzk9lDHZ