document.write( "Question 262258: The age of aman 5 year ago was seven times the age of his son. the ratio of their ages after 5 year will be 3:1. find their present ages? \n" ); document.write( "

Algebra.Com's Answer #193293 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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: The age of a man 5 year ago was seven times the age of his son.
\n" ); document.write( " the ratio of their ages after 5 year will be 3:1.
\n" ); document.write( " find their present ages?
\n" ); document.write( ":
\n" ); document.write( "Let m = the man's present age
\n" ); document.write( "let s = son's present age
\n" ); document.write( ":
\n" ); document.write( "\"The age of a man 5 year ago was seven times the age of his son.\"
\n" ); document.write( "m - 5 = 7(s - 5)
\n" ); document.write( "m - 5 = 7s - 35
\n" ); document.write( "m = 7s - 35 + 5
\n" ); document.write( "m = 7s - 30
\n" ); document.write( ":
\n" ); document.write( "\"the ratio of their ages after 5 years will be 3:1.\"
\n" ); document.write( " $\"%28m%2B5%29%2F%28s%2B5%29\"$ = $\"3%2F1\"$
\n" ); document.write( "cross multiply
\n" ); document.write( "m + 5 = 3(s+5)
\n" ); document.write( "m + 5 = 3s + 15
\n" ); document.write( "m = 3s + 15 - 5
\n" ); document.write( "m = 3s + 10
\n" ); document.write( ":
\n" ); document.write( "find their present ages?
\n" ); document.write( "Replace m with (7s-30) from the 1st statement equation
\n" ); document.write( "7s - 30 = 3s + 10
\n" ); document.write( "7s - 3s = 10 + 30
\n" ); document.write( "4s = 40
\n" ); document.write( "s = 10 yrs old is the son
\n" ); document.write( ":
\n" ); document.write( "I'll let you find the man's age \n" ); document.write( "

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