Benjamin J. answered • 04/28/23
Professional Engineer ready to lay the foundation for high school math
This question asks us to apply our knowledge of an exponential model, one of the form P=P0(r)t
Definition of the Equation P=P0(r)t
- P is our population at any point in time, what we are trying to predict with our model
- P0 is our starting population, or the population at time t=0.
- r is the rate of change in the population within a single time period.
- t is our dependent variable, what we use to predict P.
Based on the above definition, we would expect (1-0.3)t to represent the factor by which our population changes over the amount of time t, however they do not tell us a value of t... which means (I believe) that none of the answers is absolutely correct. We can however eliminate answers as definitely wrong.
D) is wrong because our factor depends on the number of years... it would not apply 3 times a year. For this to be true our exponent would need to be 3t, not t
C) is wrong because our factor depends on the number of years, not the number of 3 year time periods. For this to be true our exponent would need to be t/3, not t
B) is wrong because our factor depends on the number of years, not the number of 1.3 year periods. For this to be true our exponent would need to be t/1.3, not t
A) could be true, if t=1... so this would be the best selection
