Home. The following formula is used to calculate a population size after a certain number of years. This means that the population doubles every 5 years and so the population will quadruple (double twice) in 5*2 = 10 years. 1) After 5 hours, a bacteria culture with a growth rate of 30% per hour has grown to a population of 70,000. DT=doubling time in years. Doubling Time Calculator. Doubling Time Population Calculator A large doubling time value means slow growth, while a small doubling time value means rapid growth. Compare time difference between cities, time zones and countries of the world with our time converter. It is also applied to population growth, inflation, resource extraction, compound interest, and many other things which tend to grow over a period of time. Population Doubling time by Nation FR=fertility rate (live births/female). x(t) = x 0 × (1 + r) t. Where x(t) is the final population after time t; x 0 is the initial population; r is the rate of growth The period of time needed for an investment or money in an interest-bearing account to double in size or value is called as doubling time. A very common misuse of calculation of population doubling time (PDT) is frequently seen in many papers: number of cells at seeding time versus number of cells at harvest time. )? Bacteria Number at Time 0: Bacteria Number at Time t: Time Passed: Exponential Growth Rate: Doubling Time: Bacteria Growth Rate Formula: N t = N 0 * ( 1 + r) t where: N t: The amount at time t N 0: The amount at time 0 r: Growth rate t: Time passed. The larger the rate of growth (r), the faster the doubling time. If an archaeologist found a fossil sample that contained 25% carbon-14 in comparison to a living sample, the time of the fossil sample's death could be determined by rearranging equation 1, since N t, N 0, and t … 35 = 70/2. For example, a population with a 2% annual growth would have a doubling time of 35 years. Bacteria Growth Rate Calculator. Population Growth Formula. Key Properties of Doubling Time. For Bank A: Doubling Time = Ln (2) / Ln (1 + 10%) Doubling Time = 7.27 years For Bank B: Doubling Time = Ln (2) / Ln (1 + 12%) Doubling Time = 6.12 years So if you choose investment in A, your funds will be doubled in 7.27 years but B will double your more in 6.11 years. 3 days and 2. doubling time, Brightstorm. What was the bacteria population at the beginning of the experiment (five hours ago. Rate of growth varies considerably among organisms. Exponential Growth Calculator, Exponential Growth Problems . So the doubling time of the rabbit population is 5 years. N t is the remaining quantity after time, t t 1/2 is the half-life τ is the mean lifetime λ is the decay constant. After solving, the doubling time formula shows that Jacques would double his money within 138.98 months, or 11.58 years. 2. P=population in millions. As stated earlier, another approach to the doubling time formula that could be used with this example would be to calculate the annual percentage yield, or effective annual rate, and use it as r.The annual percentage yield on 6% compounded monthly would be 6.168%.