A colony of ants initially has 250,000 ants. The ant population declines at a rate of 2.5% each week.

Write the exponential equation to model the insect population, y, after x weeks.

1 answer

To model the decline of the ant population, we can use the exponential decay formula:

\[ y = y_0 \cdot (1 - r)^x \]

Where:

  • \(y\) is the population after \(x\) weeks,
  • \(y_0\) is the initial population,
  • \(r\) is the rate of decline (as a decimal),
  • \(x\) is the number of weeks.

Given:

  • The initial population \(y_0 = 250,000\),
  • The rate of decline \(r = 2.5% = 0.025\).

Substituting these values into the formula, we have:

\[ y = 250,000 \cdot (1 - 0.025)^x \]

This simplifies to:

\[ y = 250,000 \cdot (0.975)^x \]

This is the exponential equation that models the ant population after \(x\) weeks.