Question 1100280
Let {{{ a }}} = number of meals eaten in a restaurant
Let {{{ b }}} = number of meals eaten in a car
Let {{{ c }}} = number of meals eaten at home
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(1) {{{ a + b + c = 141 }}}
(2) {{{ b + c = a + 11 }}}
(3) {{{ a = c + 10 }}}
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Substitute (3) into (1)
(1) {{{ c + 10 + b + c = 141 }}}
and
(2) {{{ b = a + 11 - c }}}
Substitute this into (1)
(1) {{{ c + 10 + a + 11 - c + c = 141 }}}
and
(3) {{{ a = c + 10 }}}
Substitute this into (1)
(1) {{{ c + 10 + c + 10 + 11 - c + c = 141 }}}
(1) {{{ 2c + 31 = 141 }}}
(1) {{{ 2c = 110 }}}
(1) {{{ c = 55 }}}
and
(3) {{{ a = c + 10 }}}
(3) {{{ a = 55 + 10 }}}
(3) {{{ a = 65 }}}
and
(2) {{{ b = a + 11 - c }}}
(2) {{{ b = 65 + 11 - 55 }}}
(2) {{{ b = 21 }}}
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65 meals are eaten in a restaurant
21 meals are eaten in a car
55 meals are eaten at home
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check:
(1) {{{ a + b + c = 141 }}}
(1) {{{ 65 + 21 + 55 = 141 }}}
(1) {{{ 141 = 141 }}}
OK