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Population growth: There are originally 255 foxes and 104 rabbits on a particular game reserve. The fox population grows at a rate of 33 foxes per year, and the rabbits increase at a rate of 53 rabbits per year. Under these conditions, how long does it take for the number of rabbits to catch up with the number of foxes? How many of each animal will be present at that time?

Short Answer

Expert verified
It takes 8 years for rabbits to surpass foxes. There will be 519 foxes and 528 rabbits.

Step by step solution

01

Write the Initial Populations and Growth Equations

Start by noting the initial populations of the foxes and rabbits. The initial number of foxes is 255 and for rabbits, it is 104. Given that the fox population increases by 33 foxes per year, and the rabbit population grows by 53 rabbits per year, we can write the growth equations as follows: - Fox population after t years: \( F(t) = 255 + 33t \) - Rabbit population after t years: \( R(t) = 104 + 53t \)
02

Set Up the Equation for Population Equality

To find out when the rabbit population equals the fox population, we set the population equations equal to each other: \[ 255 + 33t = 104 + 53t \] This equation represents the condition when both populations are the same.
03

Solve for Time (t)

To find the value of \( t \), simplify and solve the equation: 1. Subtract \( 33t \) from both sides: \[ 255 = 104 + 20t \]2. Subtract 104 from both sides: \[ 151 = 20t \]3. Divide both sides by 20: \[ t = 7.55 \]Since time must be in whole years, round up to \( t = 8 \) years, as rabbits cannot have a fractional population.
04

Calculate the Population at That Time

Now that we know it takes 8 years for them to be equal, calculate each population:- For foxes: \[ F(8) = 255 + 33 \times 8 = 255 + 264 = 519 \]- For rabbits: \[ R(8) = 104 + 53 \times 8 = 104 + 424 = 528 \]At t = 8, rabbits have just surpassed the number of foxes.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Linear Equations
Linear equations are powerful mathematical tools that describe relationships between variables where the change occurs at a constant rate. In the context of population growth, linear equations help us model and predict future populations based on initial conditions and growth rates.
For the foxes and rabbits in the game reserve, we start with two linear equations to model their populations over time:
  • The fox population equation is given by: \( F(t) = 255 + 33t \). It starts at 255 and grows by 33 each year.
  • The rabbit population equation is \( R(t) = 104 + 53t \), starting at 104 and increasing by 53 each year.

These equations are straightforward but essential. They provide a clear way to see how each population changes year by year. The trick is to understand that the coefficients of \( t \) (33 for foxes and 53 for rabbits) dictate the pace of this growth, illustrating why mathematics describes them as linear "growths." Each year, we simply add the same amount to the starting population, reflecting the consistent growth rate.
Problem Solving
Problem-solving in algebra often involves establishing equations that reflect real-life scenarios, like the population trends of two animal species. The goal is to transform a real-world problem into an algebraic one, which can then be solved systematically.

In our problem, we want to determine how long it takes for the number of rabbits to catch up to the number of foxes. By setting the two population equations equal, we form another equation:
  • \( 255 + 33t = 104 + 53t \)

This equation allows us to determine the point in time where both populations will be equal. Solving this involves typical algebra steps:
  • Simplify by moving terms involving \( t \) to one side and constants to the other:
    \( 255 - 104 = 53t - 33t \) becomes \( 151 = 20t \).
  • Then divide to solve for \( t \), resulting in \( t = 7.55 \), which rounds up to 8 years, as we need whole years in this context.

Noting that actual populations cannot be fractional, understanding to round up to the nearest whole year is a crucial part of the problem-solving process. Ultimately, problem-solving in algebra involves recognizing when and how to apply these methods to find a logical solution.
Algebraic Modeling
Algebraic modeling involves representing real-world situations with mathematical equations, offering a precise way to analyze and project future conditions. In our exercise, each animal's population growth is represented with an algebraic model, which helps predict when their numbers will align.

By using the equations \( F(t) = 255 + 33t \) for foxes and \( R(t) = 104 + 53t \) for rabbits:
  • We're able to calculate that at \( t = 8 \), the population of rabbits ( R(t) = 528) slightly surpasses that of the foxes (\( F(t) = 519 \)).

The act of using algebra to represent and solve the problem demonstrates algebraic modeling. This approach simplifies complex real-life situations into understandable and manageable mathematical forms.

By forming and solving this model equation, we extrapolate valuable information about the future without the need to physically observe the conditions for 8 years. Thus, it saves time and provides insights that can be crucial for planning and decision-making in wildlife management, conservation efforts, and other applications. This illustrates the power and utility of algebraic modeling in practical scenarios.

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Most popular questions from this chapter

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