document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=70805>Question 70805</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0072549017/algebrahomeworkh>Beginning Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> The diamerter of the Mily Way disc is approximately 9 x 10^20 meters. How long does it take light, traveling in 10^16 m/year to travel across the diamerter of the Milky Way?\r<BR>\n" );
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document.write( "I am really confused on this one, and need some help.\r<BR>\n" );
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document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #50592 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=50592\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Look at this as a rate problem, but with much larger numbers. Use the equation d=rt. Let d=9 x 10^20 meters (diameter of galaxy) and r=10^16 m/year (speed of light in meters per year).\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%289+x+10%5E20%2A%28m%29%29%2F%2810%5E16+%28m%2Fyr%29%29+=+cross%2810%5E16%28m%2Fyr%29%2F10%5E16%28m%2Fyr%29%29%2At ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >Solve for t by dividing both sides by 10^16 m/yr<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%289+x+10%5Ecross%2820%29%28cross%28m%29%29%29%2F%2810%5Ecross%2816%29%28cross%28m%29%2Fyr%29%29+=+t ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >Divide the numbers by subtracting exponents. Remember similar units cancel<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+9+x+10%5E4+%2A%28yr%29 ALIGN=MIDDLE  ALT=\"t+=+9+x+10%5E4+%2A%28yr%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "So it takes 9 x 10^4 *(yr) or 90,000 yrs for light to go across the diameter of the Milkyway. </SPAN>\n" );
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