Answer:
So after 7 year price of the laptop will be less than $1000
Step-by-step explanation:
We have given price of the laptop is $4500
Its price is 80% of if its value in every next year
So depreciation rate = 100 - 80 =20%
For depreciation we know that
[tex]V=P(1-r)^n[/tex]
Here V is final value and P is present value
So [tex]1000=4500(1-0.2)^n[/tex]
[tex]0.2222=(0.8)^n[/tex]
Taking log both side
[tex]log0.222=nlog0.8[/tex]
n = 6.74
So after 6.74 year the price of the laptop will be less than $1000