document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=403256>Question 403256</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The peregrine falcon has been clocked in the dive at 200 miles per hour. How many feet per seconds did the bird travel?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #285165 by </B><A HREF=/tutors/aboutme.mpl?userid=rvquartz><B>rvquartz(19)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rvquartz><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=rvquartz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=285165\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> one key is to pick unit entities (by \"unit\" I mean \"1\") to cancel out the units you don't want and give you the units you DO want. \r<BR>\n" );
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document.write( "key point: anything divided by the same thing is equal to 1; so an example of a \"unit\" entity would be {1 cup / 8 ounces} or {8 ounces / 1 cup} or {12 inches / 1 foot} or {1 foot / 12 inches} - - - - ALL unit entities are equal to \"1\"\r<BR>\n" );
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document.write( "anything \"multiplied by one\" is equal to that same thing - - > so anything times a {unit entity} is that \"same thing\", just maybe expressed in different terms; for example, 12 inches is the same as 1 foot (same thing but expressed in different terms)\r<BR>\n" );
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document.write( "The terms we start with  ==> miles per hour\r<BR>\n" );
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document.write( "The terms we want to end with  ==> feet per second\r<BR>\n" );
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document.write( "So to end up with feet per second we pick unit entities to \"multiply by one\" until we have the term we want\r<BR>\n" );
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document.write( "if a term you want to eliminate is in the numerator the unit entity you pick must have that term in the denominator\r<BR>\n" );
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document.write( "if a term you want to eliminate is in the denominator then the unit entity you pick must have that term in the numerator\r<BR>\n" );
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document.write( "that process is called unit-cancellation, and it helps you end up with the units you want\r<BR>\n" );
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document.write( "also if x/y = 1, then it is also true that y/x = 1, so you are free to invert a unit entity, or an answer and still get a true result, but in the terms you want to see\r<BR>\n" );
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document.write( "We use the above principles to solve the problem now, step by step:\r<BR>\n" );
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document.write( "I don't want hours in my units, I want seconds; and 1 hour is the same as 3600 seconds because there are 60 seconds in every minute and also 60 minutes in every hour and 60 times 60 = 3600<BR>\n" );
document.write( "(200 miles / hour) * {1 hour / 3600 seconds} = 0.0555 miles per second\r<BR>\n" );
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document.write( "I don't want miles in my units, I want feet; and 1 mile is the same as 5280 feet<BR>\n" );
document.write( "(0.0555 miles / second)* {5280 feet / 1 mile} \r<BR>\n" );
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document.write( "= 293.33 feet / second, or\r<BR>\n" );
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document.write( "293.33 feet per second </SPAN>\n" );
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