293,913 views
4 votes
4 votes
A loan of $39,000 is made at 6% interest, compounded annually. After how many years will the amount due reach $55,000 or more? (Use the calculatorprovided if necessary.)Write the smallest possiblewhole number answer.

User Itxaka
by
2.9k points

1 Answer

14 votes
14 votes

Solution

Using the compound interest formula


A=P(1+(r)/(100))^n

Where

A= Amount due

P= Principal

r=rate per annum

n= number of years


\begin{gathered} P(1+(r)/(100))^n\ge A \\ \\ 39000(1+0.06)^n\ge55000 \\ \\ 1.06^(^n)\ge1.410 \\ \\ n\ge(\ln1.410)/(\ln1.06) \\ \\ n\ge5.9 \end{gathered}

The amount due will reach $55,000 or more after 6 years

User Kameswari
by
3.1k points