Question 565512
Let {{{ j }}} = James age now
Let {{{ b }}} = Bill's age now
Let {{{ f }}} = Frank's age now
given:
(1) {{{ j = 19b }}}
(2) {{{ f = j - 30 }}}
(3) {{{ j + 6 = 2*( b + 6 + f + 6 ) }}}
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This is 3 equations and 3 unknowns, so
it should be solvable
(3) {{{ j + 6 = 2*( b + 6 + f + 6 ) }}}
(3) {{{ j + 6 = 2b + 2f + 24  }}}
(3) {{{ j - 2b - 2f = 24 - 6 }}}
(3) {{{ j - 2b - 2f = 18 }}}
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(1) {{{ b = j/19 }}}
Substitute (1) and (2) into (3)
(3) {{{ j - 2b - 2f = 18 }}}
(3) {{{ j - 2*( j/19 ) - 2*( j-30 ) = 18 }}}
(3) {{{ j - 2*( j/19 ) - 2j + 60 = 18 }}}
Multiply both sides by {{{ 19 }}}
(3) {{{ 19j - 2j - 38j = -798 }}}
(3) {{{ -21j = -798 }}}
(3) {{{ j = 38 }}}
and
(1) {{{ b = j/19 }}}
(1) {{{ b = 38/19 }}}
(1) {{{ b = 2 }}}
and
(2) {{{ f = j - 30 }}}
(2) {{{ f = 38 - 30 }}}
(2) {{{ f = 8 }}}
James is 38, Bill is 2, and Frank is 8 
check:
(3) {{{ j + 6 = 2*( b + 6 + f + 6 ) }}}
(3) {{{ 38 + 6 = 2*( 2 + 6 + 8 + 6 ) }}} 
(3) {{{ 44 = 2*22 }}}
(3) {{{ 44 = 44 }}}
OK