document.write( "Question 7998: Can you please help me? I am trying to help my daughter with 8th grade algebra. Her question is this/\r
\n" ); document.write( "\n" ); document.write( "The sum of three numbers is 120. the second of the numbers is 8 less than the first, and the third is 4 more than the first. What are the first number(s)?\r
\n" ); document.write( "\n" ); document.write( "This sounds like a riddle to me \n" ); document.write( "
Algebra.Com's Answer #4384 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
First, let the three numbers be x, y, and z.\r
\n" ); document.write( "\n" ); document.write( "X is the first number.
\n" ); document.write( "y is the second number.
\n" ); document.write( "z is the third number.\r
\n" ); document.write( "\n" ); document.write( "From the description of the \"riddle\", we have:\r
\n" ); document.write( "\n" ); document.write( "\"x%2By%2Bz+=+120\" The sum of three numbers is 120.\r
\n" ); document.write( "\n" ); document.write( "\"y+=+x-8\" The second number, y, is (=) 8 less than (subtract 8 from) the first number (x).\r
\n" ); document.write( "\n" ); document.write( "\"z+=+x%2B4\" The third number, z, is (=) 4 more than (add 4 to) the first number (x).\r
\n" ); document.write( "\n" ); document.write( "So, intead of writing \"x%2By%2Bz+=+120\" we can replace the y and the z with their equivalent expressions from above:\r
\n" ); document.write( "\n" ); document.write( "\"x+%2B+%28x-8%29+%2B+%28x%2B4%29+=+120\" Now we can solve for x, the first number, and once we have that, we can easily find the 2nd and 3rd numbers.
\n" ); document.write( "Of course, your problem asks only for the first number(s)?\r
\n" ); document.write( "\n" ); document.write( "Let's solve the equation:\r
\n" ); document.write( "\n" ); document.write( "\"x+%2B+%28x-8%29+%2B+%28x%2B4%29+=+120\" Collect like-terms. Add up the x's and the numbers.\r
\n" ); document.write( "\n" ); document.write( "\"3x+-4+=+120\" Add 4 to both sides of the =.\r
\n" ); document.write( "\n" ); document.write( "\"3x+=+124\" Now divide both sides by 3.\r
\n" ); document.write( "\n" ); document.write( "x = 41 1/3 That's 41 and one third.\r
\n" ); document.write( "\n" ); document.write( "Check:\r
\n" ); document.write( "\n" ); document.write( "x+(x-8)+(x+4) = 120\r
\n" ); document.write( "\n" ); document.write( "41 1/3 + 33 1/3 + 45 1/3 = 120
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