Question 1045997
Let {{{ a }}} = Tom's age now
Let {{{ b }}} = Dad's age now
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The difference in their ages will always
be {{{ b - a }}}
So, {{{ b - a }}} is his dad's age when
Tom was born
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You are given that
(1) {{{ b - a = 27 }}}
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(2) {{{ b - 8 = 2*( a + 5 ) }}}
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(1) {{{ -a + b = 27 }}}
and
(2) {{{ b - 8 = 2a + 10 }}}
(2) {{{ -2a + b = 18 }}}
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Subtract (2) from (1)
(1) {{{ -a + b = 27 }}}
(2) {{{ 2a - b = -18 }}}
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{{{ a = 9 }}}
and
(1) {{{ b - 9 = 27 }}}
(1) {{{ b = 36 }}}
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Tom is 9 now
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check:
(1) {{{ b - a = 27 }}}
(1) {{{ 36 - 9 = 27 }}}
(1) {{{ 27 = 27 }}}
and
(2) {{{ b - 8 = 2*( a + 5 ) }}}
(2) {{{ 36 - 8 = 2*( 9 + 5 ) }}}
(2) {{{ 28 = 2*14 }}}
(2) {{{ 28 = 28 }}}
OK