Question 891918
Let {{{ m }}} = Manuel's age now
{{{ m + 5 }}} = Robert's age now
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{{{ m - 4 }}} = Manuel's age four years ago
{{{ m + 5 - 4 }}} = Robert's age four years ago
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given:
{{{ m - 4 = (3/4)*( m + 5 - 4 ) }}}
{{{ m - 4 = ( 3/4 )*( m + 1 ) }}}
{{{ 4*( m - 4 ) = 3*( m + 1 ) }}}
{{{ 4m - 16 = 3m + 3 }}}
{{{ m = 19 }}}
and
{{{ m + 5 = 24 }}}
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Manuel is 19 now
Robert is 24 now
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check:
{{{ m - 4 = ( 3/4 )*( m + 1 ) }}}
{{{ 19 - 4 = ( 3/4 )*( 19 + 1 ) }}}
{{{ 15 = (3/4)*20 }}}
{{{  4*15 = 3*20 }}}
{{{ 60 = 60 }}}
OK