Question 1108896
Let {{{ a }}} = the cost of 1 adult ticket
Let {{{ b }}} = the cost of 1 youth ticket
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(1) {{{ 25a + 40b = 620 }}}
(2) {{{ 30a + 25b = 560 }}}
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(1) {{{ 5a + 8b = 124 }}}
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Multiply both sides of (1) by {{{ 6 }}} and
subtract (2) from (1)
(1) {{{ 30a + 48b = 744 }}}
(2) {{{ -30a - 25b = -560 }}}
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{{{ 23b = 184 }}}
{{{ b = 8 }}}
and
(1) {{{ 5a + 8*8 = 124 }}}
(1) {{{ 5a = 124 - 64 }}}
(1) {{{ 5a = 60 }}}
(1) {{{ a = 12 }}}
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The cost of 1 adult ticket is $12
The cost of 1 youth ticket is $8
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get a 2nd opinion if needed