# algebra

posted by .

Susie purchased a laptop computer for \$2000 at the beginning of the year in 2008,the value of the computer decreased by 20% each year. Susie wants to purchase a new laptop computer when the value of hers falls below \$500. When will Susie be able to purchase a new laptop?

• algebra -

so you are solving

2000(.8)^n = 500
.8^n = 500/2000 = .25
take log of both sides

log .8^n = log .25
n log .8 = log .25
n = log .25/log .8 = appr 6.2 years

## Similar Questions

1. ### Intro. to Comp. -- Question

If you need a computer to carry with you to manage your daily schedule of meetings, which type of computer would be ideal in this instance?
2. ### Vocabulary

Does this sentence demonstrate the correct usage of the word "contrast"?
3. ### algebra

Robin bought a computer for \$1,250. It will depreciate, or decrease in value, by 10% each year that she owns it. a) Is the sequence formed by the value at the beginning of each year arithmetic, geometric, or neither?
4. ### algebra

computer manufacturing company would like to come up with a new laptop computer such that its monitor is 80 a square inches smaller than the present ones. Suppose the length of the monitor of the larger computer is 5 inches longer …
5. ### statistics 3

An airline promotion to business travelers is based on the assumption that no more than two-thirds of business travelers use a laptop computer on overnight business trips. 1. What is the sample proportion from an American Express-sponsored …
6. ### Math question word

Milan bought a desktop computer and a laptop computer. Before finance charges, the laptop cost \$350 less than the desktop. He paid for the computers using two different finance plans. For the desktop the interest rate was 7% per year, …
7. ### algebra

A laptop computer is purchased for \$5000 . Each year, its value is 70% of its value the year before. After how many years will the laptop computer be worth \$300 or less
8. ### Math

Shania bought a new computer for 1,550 from computer 'r' us. If the value of the computer depreciates at a rate of 5.35%per year, when will the value of the computer reach 825 ?
9. ### Math

7. The value of a computer has a decay factor of 0.85 per year. After 2 years, the computer is worth \$1445. What was the original value of the computer?
10. ### Math

Elizabeth wants to buy a new laptop computer, but she just started her baby sitting job and she hasn't earned any money yet. She figures once she starts earning income she save \$90 a month in a saving account that earns three percent …

More Similar Questions