document.write( "Question 1180388: Robert and Caleb each had a collection of rocks. Caleb had 2/9 as many rocks as Robert. When Robert lost 40 rocks, Caleb then had twice as many as Robert. How many rocks were in Robert’s collection at first? \n" ); document.write( "

Algebra.Com's Answer #810144 by ikleyn(52914) $\"\"$ $\"About$

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document.write( "Let x be the number of rocks Robert has initially.\r\n" );
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document.write( "Then Caleb's amount is    rocks.\r\n" );
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document.write( "After Robert lost 40 rocks, you have THIS EQUATION\r\n" );
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document.write( "     = 2*(x-40)\r\n" );
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document.write( "Simplify and solve\r\n" );
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document.write( "    2x = 9*2*(x-40)\r\n" );
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document.write( "    2x = 18*(x-40)\r\n" );
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document.write( "    2x = 18x - 720\r\n" );
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document.write( "    720 = 18x - 2x\r\n" );
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document.write( "    720 = 16x\r\n" );
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document.write( "     x  = 720/16 = 45.\r\n" );
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document.write( "ANSWER. Initially, Robert had 45 rocks.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved, answered and carefully explained.\r
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\n" ); document.write( "\n" ); document.write( "@mananth setup the problem INCORRECTLY, so both his/her equation and the answer are WRONG.\r
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\n" ); document.write( "\n" ); document.write( "For your safety, ignore his/her post.\r
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