69,332 views
10 votes
10 votes
Help! Using an exponential model for this data, estimate when the building value will drop below 3,000.

Help! Using an exponential model for this data, estimate when the building value will-example-1
User Pfulop
by
2.9k points

1 Answer

18 votes
18 votes

Step 1

Graph the function and generate the exponential model.

The modeled function will be;


y=12112.7(0.930332)^x

Step 2

Find when the value will drop below $3000


\begin{gathered} 3000=12112.7(0.930332)^x \\ 12112.7\cdot \:0.930332^x=3000 \\ 12112.7\cdot \:0.930332^x\cdot \:10=3000\cdot \:10 \\ 121127\cdot \:0.930332^x=30000 \\ (121127\cdot \:0.930332^x)/(121127)=(30000)/(121127) \\ 0.930332^x=(30000)/(121127) \\ x\ln \left(0.930332\right)=\ln \left((30000)/(121127)\right) \\ x=(\ln \left((30000)/(121127)\right))/(\ln \left(0.930332\right)) \\ x=19.32653 \end{gathered}

Hence the answer will be;


\begin{gathered} Year\text{ 19 tallies with 2009 and by this year the buiding value= \$3000} \\ Above\text{ this year the building value drops below \$3000} \\ Hence\text{ the answer is the value willl drop below \$3000 in 2010} \end{gathered}

Help! Using an exponential model for this data, estimate when the building value will-example-1
User Brian Beuning
by
3.5k points