document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1011686>Question 1011686</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mario decided to invest his $620 tax refund rather than spending it. He found a bank that would pay him 4% interest, compounded quarterly. Answer the following questions, assuming that Mario deposits his entire refund and does not deposit or withdraw any other amounts.<BR>\n" );
document.write( "a) Write an equation that models the growth of the investment. <BR>\n" );
document.write( "b) How many years will it take for the initial investment to double. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #627424 by </B><A HREF=/tutors/aboutme.mpl?userid=addingup><B>addingup(3677)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=addingup><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=addingup><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=627424\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is your formula:<BR>\n" );
document.write( "Number of periods:<BR>\n" );
document.write( "(log(FV/PV))/(log(1+r))<BR>\n" );
document.write( "FV is the future value, 1240<BR>\n" );
document.write( "PV is the present value, 620<BR>\n" );
document.write( "r is the interest rate per period (4% compounded quarterly= 1% per quarter)<BR>\n" );
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document.write( "(log(1240/620))/(log1+0.01)= number of periods. Use your calculator and remember to divide the number of periods by 4 to get the years.<BR>\n" );
document.write( "J </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );