document.write( "Question 817209: A shopkeeper buys 100 pens for Rs 200 and sells 20 of them at a gain of 10%. At what gain percent must he sell the remainder so as to gain 20% in all ? \n" ); document.write( "
Algebra.Com's Answer #491940 by richwmiller(17219)\"\" \"About 
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1.2*200=240
\n" ); document.write( "he pays 2 each
\n" ); document.write( "he sells 20 for 2.20 each total 44
\n" ); document.write( "he has received 44 and needs 240 total
\n" ); document.write( "240-44=196
\n" ); document.write( "he needs to sell the last 80 for 196
\n" ); document.write( "196/80=2.45 he needs to sell last 80 for 2.45 which is 22.5% gain\r
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