document.write( "Question 141348: Phil and Phyllis are siblings. Phyllis has twice as many brothers as she has sisters. Phil has the same number of brothers as sisters. How many girls and how many boys are in the family? \n" ); document.write( "
Algebra.Com's Answer #103000 by ankor@dixie-net.com(22740)\"\" \"About 
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Phil and Phyllis are siblings. Phyllis has twice as many brothers as she has sisters. Phil has the same number of brothers as sisters. How many girls and how many boys are in the family?
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\n" ); document.write( "x = no. boys
\n" ); document.write( "y = no. girls
\n" ); document.write( ":
\n" ); document.write( "Phil: (x-1) bro, y sis
\n" ); document.write( "same number bro than sis:
\n" ); document.write( "(x-1) = y
\n" ); document.write( "x - y = 1
\n" ); document.write( ":
\n" ); document.write( "Phyl: x bro, (y-1) sis
\n" ); document.write( "Twice as many bro as sis:
\n" ); document.write( "x = 2(y-1)
\n" ); document.write( "x = 2y - 2
\n" ); document.write( "x - 2y = -2
\n" ); document.write( ";
\n" ); document.write( "Using these two equation for elimination
\n" ); document.write( "x - 2y = -2
\n" ); document.write( "x - y = 1
\n" ); document.write( "-------------subtracting eliminates x
\n" ); document.write( "0 - y = -3
\n" ); document.write( "y = 3 girls
\n" ); document.write( ":
\n" ); document.write( "We know x = 2y -2:
\n" ); document.write( "x = 2(3) - 2
\n" ); document.write( "x = 4 boys
\n" ); document.write( ":
\n" ); document.write( "Therefore:
\n" ); document.write( "Phil has 3 brothers, 3 sisters
\n" ); document.write( "Phyl has 4 brothers, 2 sisters \n" ); document.write( "
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