document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1194686>Question 1194686</A>: <I><SPAN STYLE=\"word-break: break-all;\"> You are stationed at a port on the ocean. A cruise liner is sailing past your port. When it goes past you, it is traveling at a speed 30 ft/sec and is 2000 feet from shore.\r<BR>\n" );
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document.write( "A. How far will the cruise liner be from you 20 seconds from now?<BR>\n" );
document.write( "   THIS IS MY ATTEMPT:<BR>\n" );
document.write( "30 20=600<BR>\n" );
document.write( "X= 2000^2+600^2<BR>\n" );
document.write( "x=4,000,000 + 360,000 square root symbol <BR>\n" );
document.write( "x=4,360,000square root symbol<BR>\n" );
document.write( " =2088.06 ft/sec\r<BR>\n" );
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document.write( "B.Once the boat is 2500 ft away from the port, it is no, longer your responsibility to track it. Will the boat be 2500 ft away after 2 minutes?<BR>\n" );
document.write( "MY ANSWER:<BR>\n" );
document.write( "2502.88 YES THE BOAT IS FAR ENOUGH AWAY.\r<BR>\n" );
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document.write( "C. A second boat passes by your port, at a distance of 1500 feet from shore. 10 seconds later, the boat is 2000 ft away from you. How fast was the boat going?<BR>\n" );
document.write( " THIS DOESN'T MAKE  SENSE TO ME. \r<BR>\n" );
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document.write( "Could you please check my work,  I don't think I completely understand what the info & questions say.  I also think I am missing some formulas for rate/time/ distance. But I don't know.<BR>\n" );
document.write( "I am stuck. Sorry I couldn't get the equations to copy and paste correctly. Please help,  thank you\r<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 #826946 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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=826946\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "Part A\r<BR>\n" );
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document.write( "Let's say the boat is 2000 ft directly north of your location when it passes by. <BR>\n" );
document.write( "I'll also have the boat moving east (i.e. to the right).\r<BR>\n" );
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document.write( "After 20 seconds, the boat moves d = r*t = 30*20 = 600 ft east.\r<BR>\n" );
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document.write( "Your drawing would be of a right triangle with these sides<BR>\n" );
document.write( "a = 2000 = vertical leg<BR>\n" );
document.write( "b = 600 = horizontal leg<BR>\n" );
document.write( "c = unknown hypotenuse<BR>\n" );
document.write( "The 90 degree angle is north of your location.\r<BR>\n" );
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document.write( "Use the pythagorean theorem to find c.<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c+=+sqrt%282000%5E2%2B600%5E2%29 ALIGN=MIDDLE  ALT=\"c+=+sqrt%282000%5E2%2B600%5E2%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=c+=+2088.06130178211 ALIGN=MIDDLE  ALT=\"c+=+2088.06130178211\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You have the correct steps and <i>almost</i> the correct final answer. <BR>\n" );
document.write( "The units won't be \"feet per second\" because your teacher is asking about a distance, and not a speed.\r<BR>\n" );
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document.write( "Answer: Approximately 2088.06 feet\r<BR>\n" );
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document.write( "Part B\r<BR>\n" );
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document.write( "1 minute = 60 seconds<BR>\n" );
document.write( "2*1 minute = 2*60 seconds<BR>\n" );
document.write( "2 minutes = 120 seconds\r<BR>\n" );
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document.write( "Rewind the clock and place the boat directly 2000 ft north of your location again. <BR>\n" );
document.write( "After 120 seconds, the boat moves d = r*t = 30*120 = 3600 ft\r<BR>\n" );
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document.write( "Recalculate the hypotenuse c<BR>\n" );
document.write( "a = 2000<BR>\n" );
document.write( "b = 3600<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c+=+4118.2520563948 ALIGN=MIDDLE  ALT=\"c+=+4118.2520563948\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The boat is roughly 4118.25 ft away from your position after 2 minutes.<BR>\n" );
document.write( "This exceeds the 2500 ft requirement, meaning that the boat is out of your jurisdiction at this point.\r<BR>\n" );
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document.write( "I don't know how you got the 2502.88, but the portion \"yes the boat is too far away\" is correct.\r<BR>\n" );
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document.write( "Answer: The boat is further than 2500 ft at the two minute mark. The boat is no longer your responsibility to track.\r<BR>\n" );
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document.write( "Part C\r<BR>\n" );
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document.write( "Let's say the second boat is also going east. <BR>\n" );
document.write( "This boat is 1500 ft away from you when it is directly north of your position.<BR>\n" );
document.write( "Ten seconds later, it is 2000 ft away from you. \r<BR>\n" );
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document.write( "The figure of 2000 ft is the hypotenuse of the right triangle.<BR>\n" );
document.write( "The horizontal leg b is unknown<BR>\n" );
document.write( "The vertical leg of the triangle is a = 1500 ft\r<BR>\n" );
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document.write( "Solve for b using the pythagorean theorem<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b+=+sqrt%282000%5E2+-+1500%5E2%29 ALIGN=MIDDLE  ALT=\"b+=+sqrt%282000%5E2+-+1500%5E2%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=b+=+1322.8756555323 ALIGN=MIDDLE  ALT=\"b+=+1322.8756555323\"   DISABLED_style= \"max-width:90%; height:auto;\" > approximately\r<BR>\n" );
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document.write( "The boat has traveled about 1,322.8756555323 ft in 10 seconds.\r<BR>\n" );
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document.write( "distance = speed*time<BR>\n" );
document.write( "speed = distance/time<BR>\n" );
document.write( "speed = 1322.8756555323/10<BR>\n" );
document.write( "speed = 132.28756555323\r<BR>\n" );
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document.write( "Answer: The second boat is going about 132.29 ft per second\r<BR>\n" );
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document.write( "Side notes:<ul><li>I appreciate you showing your work. It's quite rare a student does that on this site.</li><li>Boat speeds are usually measured in knots, aka nautical miles per hour. A nautical mile is not the same as a statute mile (aka land based mile, aka the typical mile many people might think about)</li><li>1 statute mile = 5280 ft</li><li>There are about 6076 feet in a nautical mile</li><li>A speed of 132.29 ft/s is roughly 78.38 knots, and that is equivalent to about 90.198 mph</li><li>Regardless of the standard of using knots for ocean settings, it's best to stick to the context of the math textbook.</li><li>You can use the notation sqrt to indicate a square root. Example: sqrt(20) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2820%29 ALIGN=MIDDLE  ALT=\"sqrt%2820%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ></ul><BR>\n" );
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