document.write( "Question 1207614: Hi
\n" ); document.write( "A group of girls had an average height of 155cm.3 more girls joined the group and the average height became 157cm. If the 3 girls had the same height of 163cm each, how many girls were there at first. \n" ); document.write( "
Algebra.Com's Answer #845673 by MathTherapy(10555)\"\" \"About 
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document.write( "Hi\r\n" );
document.write( "A group of girls had an average height of 155cm.3 more girls joined the group and the average height became 157cm. If the 3 girls had the same height of 163cm each, how many girls were there at first.\r\n" );
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document.write( "Let original number of girls be G\r\n" );
document.write( "Then height of original number of girls = 155G\r\n" );
document.write( "After another 3 joined the group, height of the entire group was, 155G + 3(163) = 155G + 489\r\n" );
document.write( "Number in group after 3 more joined: G + 3\r\n" );
document.write( "We then get: \r\n" );
document.write( "                                           155G + 489 = 157(G + 3) ----- Cross-multiplying\r\n" );
document.write( "                                           155G + 489 = 157G + 471\r\n" );
document.write( "                                          155G - 157G = 471 - 489\r\n" );
document.write( "                                                 - 2G = - 18\r\n" );
document.write( "                Original number of girls, or
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