Question 1051894
Let {{{ a }}} = number in a van
Let {{{ b }}} = number in a bus
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(1) {{{ 8a + 8b = 240 }}}
(2) {{{ 4a + 1*b = 54 }}}
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Multiply both sides of (2) by {{{ 2 }}}
and subtract (2) from (1)
(1) {{{ 8a + 8b = 240 }}}
(2) {{{ -8a - 2b = -108 }}}
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{{{ 6b = 132 }}}
{{{ b = 22 }}}
and
(2) {{{ 4a + 1*22 = 54 }}}
(2) {{{ 4a = 54 - 22 }}}
(2) {{{ 4a = 32 }}}
(2) {{{ a = 8 }}}
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There were 8 students in a van and
22 students in a bus
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check:
(2) {{{ 4a + 1*b = 54 }}}
(2) {{{ 4*8 + 1*22 = 54 }}}
(2) {{{ 32 + 22  = 54 }}}
(2) {{{ 54 = 54 }}}
OK
You can check (1)