Answer:
a. Particulars Amount
Patent cost $400,000
Less: Amortization for 3 years <u>$150,000 </u> ($400,000*3/8)
Book value at the end of year 3 $250,000
Addition during Year 4 <u>$20,000 </u>
Total book value <u>$270,000</u>
Patent amortization expense for the Year 4 = Total book value / Remaining life
Patent amortization expense for the Year 4 = $270,000 / 5
Patent amortization expense for the Year 4 = $54,000
b. Adjusting Entry
Date Account titles Debit Credit
Amortization expense $54,000
Patents $54,000