A computer sells for
$
900
$900dollar sign, 900 and loses
30
%
30%30, percent of its value per year.

The value of the computer is given by 900(0.7)^t.

Step-by-step explanation:

A computer sells for $900.

If the price of the computer loses 30% of its value per year, then it is compounded every year.

Now, the price of the computer t years after it is sold will be  

900(1 - 30/100)^t = 900(0.7)^t (1)

Therefore, the value of the computer is given by the above equation (1). (Answer)