The Twisted River had approximately
5,300 Chinook salmon in 2008. The
population has been decreasing at a
rate of 8% per year. Write a function
that gives the population in terms of y
years after 2008.
I don't get it... how did u get .92?
each year p(y) = .92 p(y-1)
when y = 0, p = 5300
when y = 1, p = .92 * 5300
when y = 2, p = .92*.92 * 5300
when y = n, p = .92^n * 5300
think compound negative interest :)
p = .92^y * 5300
To write a function that gives the population in terms of y years after 2008, we can use the formula:
Population = Initial Population * (1 - Rate of decrease/100) ^ Number of years
In this case, the initial population is 5,300 Chinook salmon in 2008, and the rate of decrease is 8% per year.
The function can be written as:
```
def salmon_population(years):
initial_population = 5300
rate_of_decrease = 8
population = initial_population * ((100 - rate_of_decrease) / 100) ** years
return population
```
You can use this function by passing the number of years after 2008 as the argument. For example, to find the population after 5 years, you can call `salmon_population(5)`.
Please note that this function assumes a continuous decrease in population at a constant rate. In reality, there may be other factors affecting the actual population trend.
To write a function that gives the population in terms of y years after 2008, we can use the initial population of 5,300 Chinook salmon in 2008 and the given rate of decrease of 8% per year.
Let's call the function "population_after_years" and define it as follows:
Function: population_after_years(y)
Population = 5,300 * (1 - 0.08)^y
Return Population
In this function, "y" represents the number of years after 2008. We use the formula for compound interest to calculate the population after y years.
The formula (1 - 0.08)^y represents the multiplier that decreases the population by 8% per year. By raising (1 - 0.08) to the power of y, we account for the cumulative decrease over y years.
To find the population in terms of y years after 2008, simply call the function "population_after_years" and provide the number of years as the input. The function will return the population after y years.
For example, to find the population after 10 years (y = 10) from 2008:
Population = population_after_years(10)
Population = 5,300 * (1 - 0.08)^10
Population ≈ 3,004.56
Therefore, the population of Chinook salmon in the Twisted River would be approximately 3,004.56 after 10 years from 2008.