document.write( "Question 878901: If 5, x, y, z, 405 are the first term of a GP , find the value of x, y, z. \n" ); document.write( "
Algebra.Com's Answer #530371 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
In a GP (a geometric progression or geometric sequence) each term is equal to the previous multiplied times a constant often called the common factor and represented by \"r\" .
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\n" ); document.write( "MENTAL MATH (not showing the works of your quick mind):
\n" ); document.write( "The GP started with 5, and after multiplying times \"r\" four times we get
\n" ); document.write( "\"5r%5E4=405=810%2F2=10%2A81%2F2%2A5=5%2A81=5%2A3%5E4\" so \"r=3\" ,
\n" ); document.write( "which makes
\n" ); document.write( "\"x=5%2A3=highlight%2815%29\"
\n" ); document.write( "\"x=15%2A3=highlight%2845%29\"
\n" ); document.write( "\"y=45%2A3=highlight%28135%29\"
\n" ); document.write( "\"z=135%2A3=highlight%28405%29\"
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\n" ); document.write( "SHOW YOUR WORK:
\n" ); document.write( "Teachers like to see formulas, and formulas are an efficient way to describe ideas and concepts. What you can think through in 5 seconds can be written in formulas in 5 minutes, while it would take much longer to write an explanation of the calculations in paragraph form. However, using formulas to communicate requires sharing a common symbolic language, and we may be used to different languages.
\n" ); document.write( "\"b%5B1%5D\"= first term of the GP.
\n" ); document.write( "\"r\"= common ratio of the GP.
\n" ); document.write( "\"b%5Bn%5D=b%5B1%5Dr%5E%28n-1%29\"=\"n%5Eth\" term of the GP.
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\n" ); document.write( "\"b%5B1%5D=5\"
\n" ); document.write( "\"b%5B5%5D=405\"
\n" ); document.write( "\"5r%5E%285-1%29=405\"
\n" ); document.write( "\"5r%5E4=405\"
\n" ); document.write( "\"r%5E4=405%2F5\"
\n" ); document.write( "\"r%5E4=81\"
\n" ); document.write( "\"r=root%284%2C81%29\"
\n" ); document.write( "\"r=3\"
\n" ); document.write( "\"x=b%5B2%5D=5%2A3%5E%282-1%29=5%2A3%5E1=5%2A3=highlight%2815%29\"
\n" ); document.write( "\"y=b%5B3%5D=5%2A3%5E%283-1%29=5%2A3%5E2=5%2A9=highlight%2845%29\"
\n" ); document.write( "\"z=b%5B4%5D=5%2A3%5E%284-1%29=5%2A3%5E3=5%2A27=highlight%28135%29\"
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