use exponential models from the given sets of data to help a city developer make a prediction. the population of a grwoing city over the last 2 decades is modeled by the rounded regression equation y=34,904.80(1.05)^x. once the citys population hits 250,000, the city developer will begin contruction for a new school and hospital. if the constructio begins before 2030, the city will not yet have drawn a new city limits map and will be limited to the old city limits to choose sites for a new buildings. if contruction begins during or after 203, the new extended city limits maps will have been drawn and more options will be abailable for building. using the model, predict whether the city developer will be limited to the old city limits map for choosing contruction sites, or if they will be able to use the new city limits map and have more building options.

years since 2000:0,5,10,15,20
population: 37220, 44560, 57464, 74768, 99640
a. the city developer will be able to use the new city limits map as the citys population will hit 250,000 during or after 2030.
b the city developer will need to use the old city limits map as the citys population will hit 250,000 during or after 2030.
c. the city developer will be able to use the new city limits map as the citys population will hit 250,000 before 2030.
d. the city developer will need to use the old city limits map as the citys population will hit 250,000 before 2030.

1 answer

To determine whether the city will reach a population of 250,000 before or after 2030, we can use the given exponential model:

\[ y = 34,904.80(1.05)^x \]

where \( y \) is the population and \( x \) is the number of years since 2000. To find out when the population will reach 250,000, we can set up the equation:

\[ 250,000 = 34,904.80(1.05)^x \]

To solve for \( x \), we first divide both sides by 34,904.80:

\[ \frac{250,000}{34,904.80} = (1.05)^x \]

Calculating the left side:

\[ \frac{250,000}{34,904.80} \approx 7.15 \]

So we have:

\[ 7.15 = (1.05)^x \]

To solve for \( x \), we can take the logarithm of both sides:

\[ \log(7.15) = x \cdot \log(1.05) \]

Now, we can solve for \( x \):

\[ x = \frac{\log(7.15)}{\log(1.05)} \]

Calculating the logarithms:

  • \(\log(7.15) \approx 0.8539\)
  • \(\log(1.05) \approx 0.0212\)

Substituting these values into the equation gives:

\[ x \approx \frac{0.8539}{0.0212} \approx 40.19 \]

Since \( x \) represents the years since 2000, we convert this to a specific year:

\[ 2000 + 40.19 \approx 2040 \]

Now we can conclude that the population will reach 250,000 around the year 2040. Since 2040 is after 2030, the city developer will need to adhere to the old city limits map when choosing construction sites.

Thus, the correct answer is:

b. The city developer will need to use the old city limits map as the city’s population will hit 250,000 during or after 2030.