document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1207526>Question 1207526</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The following function models the average typing speed S, in words per minute, of a student who has been typing for t months.<BR>\n" );
document.write( "S(t) = 4 + 31 ln(t + 1),    0 ≤ t ≤ 16<BR>\n" );
document.write( "(a) What was the student's average typing speed, to the nearest word per minute, when the student first started to type?\r<BR>\n" );
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document.write( "What was the student's average typing speed, to the nearest word per minute, after 3 months?\r<BR>\n" );
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document.write( "(b) Use a graph of S to determine how long, to the nearest tenth of a month, it will take the student to achieve an average typing speed of 50 words per minute.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #845451 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20849)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=845451\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%28t%29+=+4+%2B+31%2Aln%28t+%2B+1%29 ALIGN=MIDDLE  ALT=\"S%28t%29+=+4+%2B+31%2Aln%28t+%2B+1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0+%3C=+t+%3C=+16 ALIGN=MIDDLE  ALT=\"0+%3C=+t+%3C=+16\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "(a) What was the student's average typing speed, to the nearest word per minute, when the student first started to type?\r<BR>\n" );
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document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=0 ALIGN=MIDDLE  ALT=\"t+=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%280%29+=+4+%2B+31%2A+ln%280%2B1%29=4 ALIGN=MIDDLE  ALT=\"S%280%29+=+4+%2B+31%2A+ln%280%2B1%29=4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "What was the student's average typing speed, to the nearest word per minute, after 3 months?\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=3 ALIGN=MIDDLE  ALT=\"t=3\"   DISABLED_style= \"max-width:90%; height:auto;\" > months\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=S%283%29+=+4+%2B+31%2A+ln%283%2B1%29=46.97512519471661=47 ALIGN=MIDDLE  ALT=\"S%283%29+=+4+%2B+31%2A+ln%283%2B1%29=46.97512519471661=47\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "(b) Use a graph of S to determine how long, to the nearest tenth of a month, it will take the student to achieve an average typing speed of 50 words per minute.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+55%2C+4+%2B+31%2Aln%28x+%2B+1%29%2C+50%29+ ALIGN=MIDDLE  ALT=\"+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+55%2C+4+%2B+31%2Aln%28x+%2B+1%29%2C+50%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=50+=+4+%2B+31%2Aln%28t+%2B+1%29 ALIGN=MIDDLE  ALT=\"50+=+4+%2B+31%2Aln%28t+%2B+1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=31%2Aln%28t+%2B+1%29=50-4 ALIGN=MIDDLE  ALT=\"31%2Aln%28t+%2B+1%29=50-4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28t+%2B+1%29=46%2F31 ALIGN=MIDDLE  ALT=\"ln%28t+%2B+1%29=46%2F31\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+%2B+1=e%5E%2846%2F31%29 ALIGN=MIDDLE  ALT=\"t+%2B+1=e%5E%2846%2F31%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+e%5E%2846%2F31%29+-+1 ALIGN=MIDDLE  ALT=\"t+=+e%5E%2846%2F31%29+-+1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=3.4099835872593687 ALIGN=MIDDLE  ALT=\"t=3.4099835872593687\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=3 ALIGN=MIDDLE  ALT=\"t=3\"   DISABLED_style= \"max-width:90%; height:auto;\" >months and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12.5 ALIGN=MIDDLE  ALT=\"12.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > days<BR>\n" );
document.write( "     \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+drawing%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+55%2C%0D%0Ablue%28line%283.4%2C50%2C+3.4%2C0%29%29%2C%0D%0Agraph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+55%2C+4+%2B+31%2Aln%28x+%2B+1%29%2C+50%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "  </SPAN>\n" );
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