Question 1129240
{{{ k = j + 7 }}}
{{{ m = 2k }}}
{{{ k + j + m = 77 }}}
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{{{ j = k - 7 }}}
j : k : m = j : k : 2k
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{{{ k + k - 7 + 2k = 77 }}}
{{{ 4k = 84 }}}
{{{ k = 21 }}}
and
{{{ j = k - 7  }}}
{{{ j = 21 - 7 }}}
{{{ j = 14 }}}
So, {{{ j = (2/3)*k }}}
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j : k : m = (2/3)*k : k : 2k 
j : k : m = 2k : 3k : 6k