Write the word or phrase that best completes each statement or answers the question.
-A population is increasing according to the exponential function defined by $\mathrm { y } = 3 \mathrm { e } \cdot 04 \mathrm { x }$, where $\mathrm { y }$ is in millions and $\mathrm { x }$ is the number of years. Which of the following should be done in order to answer the question "How long will it take for the population to quadruple?"
A) Solve $3 \mathrm { e } \cdot 04 \mathrm { x } = 4$.
B) Evaluate $y = 3 \mathrm { e } \cdot 04 ( 4 )$.
C) Evaluate $y = 3 e ^ { - 04 ( 1 / 4 ) }$.
D) Solve $3 \mathrm { e } \cdot 04 \mathrm { x } = 12$.

Question

Quizplus · Accepted Answer

To find out how long it will take for the population to quadruple, you need to solve for the time $x$ when the population reaches four times its initial value. Since the initial value is given as 3 million, quadrupling it would mean the population reaches 12 million. Therefore, you solve the equation $3e^{0.4x} = 12$.

Write the Word or Phrase That Best Completes Each Statement y=3e⋅04x\mathrm { y } = 3 \mathrm { e } \cdot 04 \mathrm { x }y=3e⋅04x

Write the Word or Phrase That Best Completes Each Statement $\mathrm { y } = 3 \mathrm { e } \cdot 04 \mathrm { x }$