document.write( "Question 1210616: Emir, Cillian, and Lasha are avid collectors of vintage postage stamps. During a local exhibition, they decided to donate parts of their collections to a museum. The ratio of the number of stamps Emir and Cillian gave away was 4:7, while the ratio of the number of stamps Cillian and Lasha gave away was 3:5. The number of stamps Emir gave away was 20 fewer than the number of stamps he kept for himself. Cillian kept 3/2 as many stamps as Emir kept, and Lasha kept 4/3 as many stamps as Cillian kept. After their donations, they had a combined total of 738 stamps left in their collections. How many stamps did Lasha give away? \n" ); document.write( "
Algebra.Com's Answer #854423 by KMST(5362)\"\" \"About 
You can put this solution on YOUR website!
EDIT: My calculations are wrong. See The much clearer and direct solution by iklein.\r
\n" ); document.write( "\n" ); document.write( "For every 4 stamps donated by Emir, there were 7 stamps donated by Cillian.
\n" ); document.write( "For every 3 stamps donated by Cillian, there were 5 stamps donated by Lasha.
\n" ); document.write( "That means that for every \"7%2A3=21\" stamps given away by Cillian, there were
\n" ); document.write( "\"4%2A3=12\" stamps given away by Emir, and
\n" ); document.write( "This is wrong --> \"5%2A3=15\" stamps given away by Lasha.
\n" ); document.write( "It should have been \"5%2A7=35\" .
\n" ); document.write( "
\n" ); document.write( "Let us make
\n" ); document.write( "the number of stamps donated by Emir \"%22=%22\"\"12x\" ,
\n" ); document.write( "the number of stamps given by Cillian \"%22=%22\"\"21x\" , and
\n" ); document.write( "the number of stamps given by Lasha \"%22=%22\"\"15x\" ,
\n" ); document.write( "
\n" ); document.write( "EDIT:Here is where the other solutions are better (besides having no mistakes). I insisted on calculating number of stamps kept based on \"x\" , but that unnecessarily complicates the calculations.\r
\n" ); document.write( "\n" ); document.write( "The number of stamps Emir gave away was 20 fewer than the number of stamps he kept for himself means Emir kept \"12x%2B20\" stamps. See the much clearer and direct solution by Iklein.\r
\n" ); document.write( "\n" ); document.write( "Cillian kept 3/2 as many stamps as Emir, Cillian and Lasha kept means
\n" ); document.write( "Cillian kept \"%283%2F2%29%2812x%2B20%29=18x%2B30\" stamps.
\n" ); document.write( "
\n" ); document.write( "Lasha kept 4/3 as many stamps as Cillian kept means
\n" ); document.write( "Lasha kept \"%284%2F3%29%2818x%2B30%29=24x%2B40\" stamps.\r
\n" ); document.write( "\n" ); document.write( "After their donations, the total number of stamps Emir, Cillian and Lasha had left in their collections was
\n" ); document.write( "\"%2812x%2B20%29%2B%2818x%2B30%29%2B%2824x%2B40%29=738\"<-->\"%2812%2B18%2B24%29x%2B20%2B30%2B40=738\"-->\"54x%2B90=738\"-->\"54x=738-90\"-->\"54x=648\"-->\"x=648%2F54\"-->\"x=12\"
\n" ); document.write( "
\n" ); document.write( "Lasha gave away\"15%2A12=highlight%28180%29\" stamps.
\n" ); document.write( "
\n" ); document.write( "In table form that looks like:
\n" ); document.write( " -->
\n" ); document.write( "After solving \"%2812x%2B20%29%2B%2812x%2B20%29%2B%2824x%2B40%29=738\"->->-> \"x=12\" , we can substitute that value to get
\n" ); document.write( "
\n" ); document.write( "We can calculate the number of stamps each one originally had, and the number each donated,
\n" ); document.write( "but we are only asked for the number Lasha donated: \"15%2A12=180\".
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