1. O

    Bacteria colony growth

    Hi, I hope someone can help. I'm trying to solve the following problem: Apparently I have to create a function which would subtract K(t) from N(t), while taking into account that N(t) starts 60 minutes before K(t). Following that, I would need to use this function to find the critical values...
  2. M

    Calculate % Growth and Net increase

    This is most likely simplistic but is giving me trouble. I'm trying to find the best way to set up a formula to help calculate the % of growth and the overall net increase from this group of numbers. Someone had sent me the following as an example and came up with a 0.4% overall growth and a net...
  3. M

    Exponential Growth and Decay Problem.

    At the start of an experiment, 2 x 10^4 bacteria are present in a colony. Eight hours later, the population is 3 x 10^4. (a) determine the growth constant k. (b) what was the population two hours after the start of the experiment? Formula for this: N=N_o(e)^(kt) N= is the sum of answer...
  4. G

    Exponential Growth

    Been stuck on this on this Q for hours tried many things would be appreciated if i could get some help Refer to picture Thanks Giovanni55 :)
  5. A

    Exponential Growth and Decay

    I've been having trouble with this math problem: Assume that in a chemical reaction a certain substance decomposes at a rate proportional to the amount present. Assume that the initial quantity of 10,000 grams is reduced to 1,000 in 5 hours. How much would be left of the initial quantity of...
  6. I

    Give the starting value a, the growth factor for the given exponential function

    Q = 13 * 2(t/10)-1 has: a = b = Q = (1/7)*(cubed root of 8t) has: a= b= Q(t) = 0.0033(2.26)-4t The initial value is a = The growth factor is b= The growth rate is r = I'm at a loss as to how to solve these problems. Do I need to get it to abt form?
  7. R

    An exponential function with a growth factor between 0 and 1

    1. An exponential function with a growth factor between 0 and 1 A. is decreasing B. is constant C. is increasing D. sometimes decreases and sometimes increases 2. An exponential function with a growth factor greater than 1 A. is decreasing B. is constant C. is increasing D...
  8. S

    Help with uninhibited growth and half life problem?

    I've been trying to do these for some time now, but not able to get the right answer. I would like some external input in this. 1. The population of a colony of mosquitoes obeys the law of uninhibited growth. If there are 1000 mosquitoes initially and there are 1800 after 1 day, what is the...
  9. F

    Tricky Percent Growth Problem

    I’ve gota percent growth problem that seems like it should be very basic, but myresults indicate there's something wrong with my methodology (I've attached asummary of the problem). Guidance greatly appreciated!
  10. S

    ODE on population growth

    i have this equation and asked to find and the answer for i) is 0 ii) is 2 im a bit confused with the answer of ii) this is the phase plot of the given ODE when y(0) = 3 dy/dt is a negative value meaning decreasing value of population which means the population will go to zero?? but...
  11. A

    Macroeconomics Maths - MRW Growth Model Derivatives

    Hi all I am confused with taking the derivatives and calculating the elasticities of equations from the Mankiw Romer Weil growth model. I have attached the question and and will screenshot the required equations. I also put a link to MRW paper. Any help would be great! Thanks in advance!!!! A...
  12. L

    Please check my rate of growth

    I know I got the 1st part of the problem right but I am not sure if I am correctly getting the "rate of growth": Thx!
  13. A

    Find the slope of a curved line showing population growth

    There is an example in the online calculus course I'm taking that shows a graph which shows y=population and x=number of years. In the example it shows a point which represents the population at that time. So at point "A" the year was 1985 and the population was 3600. Then is says the slope of...
  14. J

    Geometric growth and decay

    I need help with this question....If someone can show me the steps on how to it that would be awesome! A small square picture measures 3 1/2 inches by 3 1/2 inches. A photocopier is set to produce copies that are an enlargement of the original such that both the length and width are increased...
  15. DexterOnline2

    Present value of growing annuity when deferred growth doesn't coincide with payments

    Help me find present value of an annuity in amount of 1000 dollars coming in at the end of each month for 3.5 years Payments grow at a nominal rate of 6% compounded monthly each year where first growth begins at the 7th payment and stays at the same growth rate for the remaining year, the next...
  16. C

    Growth and Decay

    In 1985, there were 285 cell phone subscribers in the small town of Centerville. The number of subscribers increased by 75% per year after 1985. How many cell phone subscribers were in Centerville in 1994? (Don't consider a fractional part of a person.) Use y= a(1+r)x​
  17. J

    Exponential growth problem - real estate values

    I wonder whether anyone can help with an exponential growth problem that is not supposed to involve logarithms (we haven't learned them yet!). The problem says,"From 2000 to 2010, median home prices in Austin, Texas rose an average of 7.2% per year. Find the monthly percent increase in the...
  18. Y

    Trying to find time period for portfolio growth

    Hi all, Trying to calculate for different portfolio growth, and the time period required to reach a sum, the equation looks something like this 100(1.08)^x + 200 (1.07)^x + 300 (1.01)^ x >= 2000 Solve for x, of which ^ means to the power to and x is time period. Thanks!
  19. T

    calculating compound interest with non-linear interest growth

    Hello, I would really appreciate some help with the following problem. I'd like to derive a formula to determine the value of an investment where the annual yield increases by a fixed percentage each year. The interest paid is re-invested each year. The standard compounding formulas use a fixed...
  20. nycmath

    Find Rate For Population Growth

    I am doing a self-study and review of calculus 1 material. I came across this question. Given p(t) = 500[1 + (4t/(50+t^2)] Note that t is measured in hours. Find the rate at which the population is growing when t = 2. Must I find the derivative of p(t) before replacing t with 2 or...