document.write( "Question 924441: Preet is 5 years older than Ben. She is also 7 years older than Jessy. The sum of their age 21. How old is each person?\r
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Algebra.Com's Answer #560827 by wangsol(2)\"\" \"About 
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Preet is 5 years older than Ben:
\n" ); document.write( "P=B+5 ------eq. 1\r
\n" ); document.write( "\n" ); document.write( "She is also 7 years older than Jessy:
\n" ); document.write( "P=J+7
\n" ); document.write( "J=P-7 ------eq. 2\r
\n" ); document.write( "\n" ); document.write( "The sum of their age 21:
\n" ); document.write( "P+B+J=21 ------eq. 3\r
\n" ); document.write( "\n" ); document.write( "eq. 1 in eq. 2:
\n" ); document.write( "if P=B+5
\n" ); document.write( "then J=B+5-7 ------eq. 4\r
\n" ); document.write( "\n" ); document.write( "substitute eq. 1 & eq. 4 in eq. 3:(solve for B)
\n" ); document.write( "B+5+B+B+5-7=21
\n" ); document.write( "(B+B+B)+(5+5-7)=21
\n" ); document.write( "3B+3=21
\n" ); document.write( "3B=21-3
\n" ); document.write( "3B=18
\n" ); document.write( "B=18/3
\n" ); document.write( "B=6\r
\n" ); document.write( "\n" ); document.write( "substitute B=6 in eq. 1 & eq. 4:
\n" ); document.write( "P=6+5=11
\n" ); document.write( "J=6+5-7=4\r
\n" ); document.write( "\n" ); document.write( "therefore:
\n" ); document.write( "P=11, B=6, J=4\r
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