document.write( "Question 1006157: I cannot seem to find how to resolve this question.
\n" ); document.write( "I made average pies, tried adding equations. I do not know what to do next! Thanks for your help.\r
\n" ); document.write( "\n" ); document.write( "The average between a and b is 9, between b and c is 6, between c and d is 15. What is the average between d and a?\r
\n" ); document.write( "\n" ); document.write( "Thank you so very much!
\n" ); document.write( "Caroline
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Algebra.Com's Answer #622317 by MathTherapy(10555) $\"\"$ $\"About$

You can put this solution on YOUR website!

\n" ); document.write( "I cannot seem to find how to resolve this question.
\n" ); document.write( "I made average pies, tried adding equations. I do not know what to do next! Thanks for your help.\r
\n" ); document.write( "\n" ); document.write( "The average between a and b is 9, between b and c is 6, between c and d is 15. What is the average between d and a?\r
\n" ); document.write( "\n" ); document.write( "Thank you so very much!
\n" ); document.write( "Caroline
\n" ); document.write( "

If 9 is the average of a and b, then sum of a and b is 2(9), or 18, so a + b = 18______b = 18 - a ------- eq (i)
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document.write( "If 6 is the average of b and c, then sum of b and c is 2(6), or 12, so b + c = 12 -------- eq (ii)
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document.write( "If 15 is the average of c and d, then sum of c and d is 2(15), or 30, so c + d = 30 ------ eq (iii)
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document.write( "18 – a + c = 12 ------- Substituting 18 – a for b in eq (ii)
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document.write( "c = a – 18 + 12
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document.write( "c = a – 6 -------- eq (iv)
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document.write( "a – 6 + d = 30 ------- Substituting a - 6 for c in eq (iii)
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document.write( "a + d = 30 + 6
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document.write( "a + d = 36
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document.write( "Average of a + d: , or , or  \n" );
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