Answer:
a. $395,000
Explanation:
Since the depreciating method is practiced in a straight-line basis, the equation for the value of the building as a function of the time in years (V(t)) is:
[tex]V(t) = -kt + C[/tex]
Where k is the yearly depreciation rate of $15,000 per year and C is the initial cost.
For t = 25 years, V(t) = $20,000. Thus:
[tex]V(t) = -15,000t + C\\V(25) = 20,000 = -15,000*25 +C\\C= 20,000 + 15,000*25\\C= 395,000[/tex]
The original cost of the building was $395,000