document.write( "Question 887985: Father says to his daughter.When i was your age you were 4 years old.When I will be 79 you will be my present age.
\n" ); document.write( "What are their present ages.
\n" ); document.write( "Vinod \n" ); document.write( "
Algebra.Com's Answer #537058 by ankor@dixie-net.com(22740)\"\" \"About 
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Father says to his daughter, \"When I was your age, you were 4 years old. When I will be 79 you will be my present age.\"
\n" ); document.write( "What are their present ages.
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\n" ); document.write( "let f = father's present age
\n" ); document.write( "let d = daughter's \" \"
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\n" ); document.write( "\"When I was your age, you were 4 years old.\"
\n" ); document.write( "(d-4) = the difference in their ages
\n" ); document.write( "therefore we can write an equation
\n" ); document.write( "f - 2(d-4) = 4
\n" ); document.write( "f - 2d + 8 = 4
\n" ); document.write( "f - 2d = 4 - 8
\n" ); document.write( "f = 2d - 4
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\n" ); document.write( "\" When I will be 79 you will be my present age.\"
\n" ); document.write( "f = 79 - (d-4)
\n" ); document.write( "f = 79 - d + 4
\n" ); document.write( "f = 83 - d
\n" ); document.write( "Replace f with (2d-4)
\n" ); document.write( "2d - 4 = 83 - d
\n" ); document.write( "2d + d = 83 + 4
\n" ); document.write( "3d = 87
\n" ); document.write( "d = 87/3
\n" ); document.write( "d = 29 yrs is the daughter's age
\n" ); document.write( "then
\n" ); document.write( "83 - 29 = 54 yrs is fathers age
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\n" ); document.write( "Check this: 54 - 29 = 25 years is the difference in their ages
\n" ); document.write( "When Dad is daughter's age (29), daughter will be 4 \n" ); document.write( "
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