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 #845584 by ikleyn(52832) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "A group of girls had an average height of 155cm. 3 more girls joined the group
\n" ); document.write( "and the average height became 157cm. If the 3 girls had the same height of 163cm each,
\n" ); document.write( "how many girls were there at first.
\n" ); document.write( "~~~~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "

\r\n" );
document.write( "Let n girls there were at first.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Then an equation to find n is\r\n" );
document.write( "\r\n" );
document.write( "     = 157.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Simplify and find n\r\n" );
document.write( "\r\n" );
document.write( "    155n + 3*163 = 157*(n+3)\r\n" );
document.write( "\r\n" );
document.write( "    155n + 489 = 157n + 471\r\n" );
document.write( "\r\n" );
document.write( "    489 - 471 = 157n - 155n\r\n" );
document.write( "\r\n" );
document.write( "        18    =     2n\r\n" );
document.write( "\r\n" );
document.write( "         n    =     18/2 = 9.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "ANSWER.  n = 9.   At first, there were 9 girls.\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( "Solved.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "--------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "It is a typical problem on average.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "To see many other similar (and different) solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on average scores, weight, height and temperature\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on average scores\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on average age \r
\n" ); document.write( "\n" ); document.write( "    - Miscellaneous problems on average values \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook, handbook, tutorials and (free of charge) home teacher.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Learn the subject from there and become an expert.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );