document.write( "Question 1147027: Hi
\n" ); document.write( "A B and C had 181 cookies at first. A gave away 20% of her cookies while B bought 28 more cookies. C also bought more cookies and had 4 times as many as before. Then the ratio of the number of cookies A B C had was 2:5:8 respectively. How many cookies did B have at first.\r
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Algebra.Com's Answer #768317 by ikleyn(52798) $\"\"$ $\"About$

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document.write( "Let \"a\", \"b\" and \"c\" be the numbers of cookies that A, B and C had originally.\r\n" );
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document.write( "The first equation is\r\n" );
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document.write( "    a + b + c = 181.    (1)\r\n" );
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document.write( "After all events, A had  0.8a cookies,  B had (b+28)  and C had 4c cookies.\r\n" );
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document.write( "We are given this long proportion  0.8a : (b+28) : 4c = 2 : 5 : 8.\r\n" );
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document.write( "It means that\r\n" );
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document.write( "    0.8a = 2x,\r\n" );
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document.write( "    b+28 = 5x\r\n" );
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document.write( "    4c = 8x\r\n" );
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document.write( "for some unknown number x.\r\n" );
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document.write( "From these equations,  \r\n" );
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document.write( "    a = ,             (2)\r\n" );
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document.write( "    b = 5x - 28           (3)\r\n" );
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document.write( "    c = 2x.               (4)\r\n" );
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document.write( "Substitute it into equation (1). You will get\r\n" );
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document.write( "     + (5x-28) + 2x = 181.\r\n" );
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document.write( "Now solve this equation and find \"x\".\r\n" );
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document.write( "Then find \"a\", \"b\" and \"c\" from (2), (3) and (4).\r\n" );
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document.write( "Check if your answer are INTEGER numbers.\r\n" );
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