Question 1118198
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A movie star, unwilling to give his age, posed the
following riddle to a gossip columnist: “Seven years ago, I
was eleven times as old as my daughter. Now I am four times
as old as she is.” How old is the movie star?

Please, and recommend me a book of that kind of problems, thanks!
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y, Movie Star
x, Daughter

The literal description:  {{{system(y-7=11(x-7),y=4x)}}}


{{{y-7=11x-77}}}
{{{4x-7=11x-77}}}
{{{-7+77=7x}}}
{{{70=7x}}}
{{{highlight(x=10)}}}--------daughter's age now
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{{{y=4x}}}
{{{y=4*10}}}
{{{highlight(y=40)}}}--------movie star's age now




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Age Word description problems such as these can be found in both old and in new Algebra 1 and Algebra 2 textbooks.  How old the book will usually not matter.