Question 1127423
let ratios of eldest son, youngest son, and daughter be:
a:b:c
---------------
{{{ a/c = 2/1 }}}
{{{ b/c = 5/3 }}}
{{{ a/b }}} =?
----------------------
{{{ b/c = 5/3 }}}
{{{ b = (5/3)*c }}}
{{{ c = (3/5)*b }}}
----------------------
{{{ a/c = 2/1 }}}
{{{ a/((3/5)*b) = 2 }}}
Multiply both sides by {{{ 3/5 }}}
{{{ a/b = 6/5 }}}
eldest son to youngest son = 6:5
----------------------------------------
check:
ratios are 6:5:3
a/c is {{{ 6/3 = 2/1 }}}
OK