Question 1103807
Let {{{ a }}} = Harry's age now
Let {{{ b }}} = Ian's age now
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(1) {{{ a = b + 20 }}}
(2) {{{ b + 5 = (3/5)*( a + 5 ) }}}
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(2) {{{ 5*( b + 5 ) = 3*( a + 5 ) }}}
(2) {{{ 5b + 25 = 3a + 15 }}}
(2) {{{ 3a - 5b = 10 }}}
Substitute (1) into (2)
(2) {{{ 3*( b + 20 )  - 5b = 10 }}}
(2) {{{ 3b + 60 - 5b = 10 }}}
(2) {{{ 5b - 3b = 50 }}}
(2) {{{ 2b = 50 }}}
(2) {{{ b = 25 }}}
and
(1) {{{ a = b + 20 }}}
(1) {{{ a = 25 + 20 }}}
(1) {{{ a = 45 }}}
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Harry is 45 now
Ian is 25 now
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check:
(2) {{{ b + 5 = (3/5)*( a + 5 ) }}}
(2) {{{ 25 + 5 = (3/5)*( 45 + 5 ) }}}
(2) {{{ 30 = (3/5)*50 }}}
(2) {{{ 30 = 30 }}}
OK