Question 1128362
Let {{{ x }}} = his age
{{{ (1/6)*x + (1/12)*x + (1/7)*x + 5 + (1/2)*x + 4 = x }}}
Multiply both sides by {{{ 6*7*12 }}}
{{{ 84x + 42x + 72x + 2520 + 252x + 2016 = 504x }}}
{{{ 54x = 4536 }}}
{{{ x = 84 }}}
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check:
His son lived to half this age or {{{ 42 }}}
{{{ 14 + 7 + 12 + 5 + 42 + 4 = 84 }}}
{{{ 84 = 84 }}}
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Feel free to get a 2nd opinion, too