Question 1157378
Let {{{ x }}} = Frank's age
{{{ 2x + 4 }}} = Charlie's age
{{{ x + 3 }}} = Bob's age
{{{ 9 }}} = Bob's age
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{{{ x + 3 = 9 }}}
{{{ x = 6 }}}
{{{ 2x + 4 = 2*6 + 4 }}}
{{{ 2x + 4 = 12 + 4 }}}
{{{ 2x + 4 = 16 }}}
Charlie is 16