Question 1059292
Let {{{ a }}} = Anthony's age now
Let {{{ b }}} = his grandson's age now
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(1) {{{ a = b + 50 }}}
(2) {{{ a - 20 = 6*( b - 20 ) }}}
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Plug (1) into (2)
(2) {{{ b + 50 - 20 = 6*( b - 20 ) }}}
(2) {{{ b + 30 = 6b - 120 }}}
(2) {{{ 5b = 150 }}}
(2) {{{ b = 30 }}}
and
(1) {{{ a = b + 50 }}}
(1) {{{ a = 30 + 50 }}}
(1) {{{ a = 80 }}}
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Anthony is 80
His grandson is 30
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check:
(2) {{{ a - 20 = 6*( b - 20 ) }}}
(2) {{{ 80 - 20 = 6*( 30 - 20 ) }}}
(2) {{{ 60 = 6*10 }}}
(2) {{{ 60 = 60 }}}
OK