Question

A laptop computer is purchased for $4700. Each year, it’s value is 80% of its value the year before. After how many years will the laptop computer be worth $1000 or less?

Answer 1

1 year

Explanation:

4700 x .8= 3760

4700 - 3760 = 940$

In 1 year the laptop will be $940

Answer 2

Step 1:

Let x = number of years

Let y = Value of the laptop after x years

Step 2:

Write an equation that expresses the value of the laptop after x years y = 0.8((4700)x)

Step 3:

Set the equation equal to 1000 and solve for x

1000 = 0.8((4700)x)

1 = 0.8(4700)x

1/0.8 = 4700x

1.25 = 4700x

x = (1.25/4700)

Answer: The laptop will be worth $1000 or less after 0.0026608 years.