Create an exponential function to represent a population of 50 insects that is growing at a rate of 7%. Which of the following functions is accurate?

f(x) = 50(1.7)^x
f(x) = 50(0.93)^x
f(x) = 50(0.07)^x
f(x) = 50(1.07)^x

1 answer

To represent a population that is growing exponentially, you can use the standard formula:

\[ P(t) = P_0 \cdot (1 + r)^t \]

where:

  • \( P(t) \) is the population at time \( t \),
  • \( P_0 \) is the initial population,
  • \( r \) is the growth rate (expressed as a decimal),
  • \( t \) is the time in appropriate units (for example, days, months, etc.).

In this case:

  • The initial population, \( P_0 \), is 50 insects.
  • The growth rate, \( r \), is 7%, which is 0.07 in decimal form.

Substituting the values into the formula gives:

\[ P(t) = 50 \cdot (1 + 0.07)^t \] \[ P(t) = 50 \cdot (1.07)^t \]

Thus, the correct function representing the population of 50 insects growing at a rate of 7% is:

f(x) = 50(1.07)^x