document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=414458>Question 414458</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A $3.00 toll is charged to cross the bridge from Sanibel Island to mainland Florida. A six-month pass, costing $15.00, reduces the toll to $.50. A one-year pass, costing $150, allows for free crossings. How many crossings per year does it take, on average, for two six-months passes to be the most economical choice? Assume a constant number of trips per month, Show work and explain answer.  \r<BR>\n" );
document.write( "\n" );
document.write( "I am not sure what formula to use for this problem. Please Help! :/ </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #290764 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=290764\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A $3.00 toll is charged to cross the bridge from Sanibel Island to mainland Florida. A six-month pass, costing $15.00, reduces the toll to $.50. A one-year pass, costing $150, allows for free crossings. <BR>\n" );
document.write( "--------------------------<BR>\n" );
document.write( "How many crossings per year does it take, on average, for two six-months passes to be the most economical choice? <BR>\n" );
document.write( "Assume a constant number of trips per month, Show work and explain answer. <BR>\n" );
document.write( "--------<BR>\n" );
document.write( "Cost with two 6-month passes = 30 + 0.50x for x crossings in one year.<BR>\n" );
document.write( "Cost of unlimited crossings for one year: $150<BR>\n" );
document.write( "Cost of x crossings for one year: 3x<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "Solve for \"x\":<BR>\n" );
document.write( "30+0.5x < 150<BR>\n" );
document.write( "0.5x < 120<BR>\n" );
document.write( "x < 240 (2 six-month passes cheaper if # of crossings is less than 120)<BR>\n" );
document.write( "----<BR>\n" );
document.write( "30+0.5x < 3x<BR>\n" );
document.write( "2.5x > 30<BR>\n" );
document.write( "x > 12<BR>\n" );
document.write( "----<BR>\n" );
document.write( "So, 2 six-mth passes cheaper if 12 < x < 240<BR>\n" );
document.write( "============================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "============= </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );