Question 838868
Let {{{ a }}} = number of adults who attended
Let {{{ c }}} = number of children who attended
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(1) {{{ a + c = 600 }}}
(2) {{{ 6a + 3c = 2940 }}}
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Subtract (1) from (2)
(2) {{{ 2a + c = 980 }}}
(1) {{{ -a - c =- 600 }}}
{{{ a = 380 }}}
and
(1) {{{ 380 + c = 600 }}}
(1) {{{ c = 220 }}}
220 children attended
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check:
(2) {{{ 2*380 + 220 = 980 }}}
(2) {{{ 760 + 220 + 980 }}}
(2) {{{ 980 = 980 }}}
OK