document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=195095>Question 195095</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 4. On October 1, a gardener plants 20 bulbs. On October 2, she plants 23<BR>\n" );
document.write( "bulbs. On October 3, she plants 26 bulbs. She continues in this pattern<BR>\n" );
document.write( "until October 15, on which she plants the last bulbs.\r<BR>\n" );
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document.write( "a. Write an explicit formula to model the number of bulbs she plants<BR>\n" );
document.write( "each day.<BR>\n" );
document.write( "b. Write a recursive formula to model the number of bulbs she plants<BR>\n" );
document.write( "each day.<BR>\n" );
document.write( "c. How many bulbs will the gardener plant on October 15?<BR>\n" );
document.write( "d. What is the total number of bulbs she plants from October 1 to<BR>\n" );
document.write( "October 15, inclusive? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #146350 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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=146350\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a(n) =a(1) + (n-1) d,,,,where  a(n) =  nth entry,,n=no entries,,d = difference  between  entries<BR>\n" );
document.write( ".<BR>\n" );
document.write( "a(15) = 20 + (15-1) 3 = 20 + 42 = 62<BR>\n" );
document.write( ".<BR>\n" );
document.write( "recursive,  a(n) =  a (n-1) +d<BR>\n" );
document.write( ".<BR>\n" );
document.write( "sum = n(a(1) +a(n) ) /2= 15 *( 20 +62)/2 = 615<BR>\n" );
document.write( ". </SPAN>\n" );
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