Joshua just purchased a 4-year-old car for $12,000. He was told that this make and model depreciates exponentially at a rate of 5.8% per year. What was the original price to the nearest hundred dollars?

2 Answers
Feb 27, 2018

$15000$15000

Explanation:

After 4 years, the car is worth $12000$12000.
Work backwards.

33 "years"=12000 xx 1.058= $12696years=12000×1.058=$12696

22 "years"= 12696 xx 1.058= $13432.368years=12696×1.058=$13432.368

11 "year"= 13432.368 xx 1.058= $14211.445344year=13432.368×1.058=$14211.445344

Original: 14211.445344 xx 1.058= $15035.70917414211.445344×1.058=$15035.709174

to nearest $100$100
=$15000=$15000

-Fish

Feb 27, 2018

Write an equation to satisfy the word problem:

12000=x(1-0.058)^(4)12000=x(10.058)4

Solve:

0.7874x=120000.7874x=12000

x~~15240.03x15240.03

The price was approximately $15240.03$15240.03, and to the nearest hundred dollars is $15200$15200.