After a special medicine is introduced into a petri dish containing a bacterial culture, the number of bacteria remaining in the dish decreases rapidly.The population loses 41 of its size every 44 seconds. The number of remaining bacteria can be modeled by a function, N, which depends on the amount of time, t (in seconds).Before the medicine was introduced, there were 11,880 bacteria in the Petri dish.Write a function that models the number of remaining bacteria t seconds since the medicine was introduced.N(t)=□
Q. After a special medicine is introduced into a petri dish containing a bacterial culture, the number of bacteria remaining in the dish decreases rapidly.The population loses 41 of its size every 44 seconds. The number of remaining bacteria can be modeled by a function, N, which depends on the amount of time, t (in seconds).Before the medicine was introduced, there were 11,880 bacteria in the Petri dish.Write a function that models the number of remaining bacteria t seconds since the medicine was introduced.N(t)=□
Identify initial amount and rate: Identify the initial amount of bacteria and the rate of decrease.The initial amount of bacteria a is given as 11,880. The bacteria population decreases by 41 of its size every 44 seconds, which means the remaining fraction of the population after each decrease is 43 (since 1−41=43).
Determine decay factor: Determine the decay factor b. The decay factor b is the fraction of the population that remains after each time interval. In this case, every 44 seconds, the population retains 43 of its size. Therefore, b=43.
Write exponential decay function: Write the exponential decay function.The general form of an exponential decay function is N(t)=a(b)t, where N(t) is the number of bacteria at time t, a is the initial amount, b is the decay factor, and t is the time in the same units as the decay interval. However, since the decay happens every 44 seconds, we need to adjust the exponent to reflect the number of 44-second intervals that have passed. This means we divide t by 44 to get the number of intervals.
Write final function: Write the final function.Using the values from the previous steps, the function that models the number of remaining bacteria t seconds since the medicine was introduced is:N(t)=11,880×(43)44t
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