Question 1050652
Let {{{ a }}} = kid's present age
Let {{{ b }}} = mother's present age
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(1) {{{ a = (1/5)*b }}}
(2) {{{ a + 6 = (1/3)*( b + 6 ) }}}
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(1) {{{ b = 5a }}}
(2) {{{ 3a + 18 = b + 6 }}}
(2) {{{ b = 3a + 12 }}}
Substitute (1) into (2)
(2) {{{ 5a = 3a + 12 }}}
(2) {{{ 2a = 12 }}}
(2) {{{ a = 6 }}}
and
(1) {{{ b = 5a }}}
(1) {{{ b = 5*6 }}}
(1) {{{ b = 30 }}}
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The kid is 6
The mother is 30
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check:
(2) {{{ a + 6 = (1/3)*( b + 6 ) }}}
(2) {{{ 6 + 6 = (1/3)*( 30 + 6 ) }}}
(2) {{{ 12 = (1/3)*36 }}}
(2) {{{ 36 = 36 }}}
OK