Question 686588
Let {{{ n }}} = number of years ago that the 
oriental rug 4 times as old as the persian rug
given:
{{{ 52 - n = 4*( 16 - n ) }}}
{{{ 52 - n = 64 - 4n }}}
{{{ 3n = 64 - 52 }}}
{{{ 3n = 12 }}}
{{{ n = 4 }}}
4 years ago, the oriental rug was 4 times as old as the persian rug
check:
{{{ 52 - n = 4*( 16 - n ) }}}
{{{ 52 - 4 = 48 }}}
{{{ 16 - 4 = 12 }}}
{{{ 48 = 4*12 }}}
{{{ 48 = 48 }}}
OK