Question 1059141
Let {{{ a }}} = number of adults
Let {{{ b }}} = number of children
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(1) {{{ a + b  = 11 }}}
(2) {{{ 22a + 15b = 228 }}}
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To solve, multiply both sides of (1) by {{{ 15 }}}
and subtract (1) from (2)
(2) {{{ 22a + 15b = 228 }}}
(1) {{{ -15a - 15b = -165 }}}
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{{{ 7a = 63 }}}
{{{ a = 9 }}}
and
(1) {{{ a + b  = 11 }}}
(1) {{{ 9 + b = 11 }}}
(1) {{{ b = 2 }}}
There are 2 children and 9 adults