Question 1139825
Let {{{ a }}} = number of $5 bills
Let {{{ b }}} = number of $20 bills
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(1) {{{ a = b + 47 }}}
(2) {{{ 5a + 20b = 1710 }}}
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(1) {{{ a - b = 47 }}}
(2) {{{ a + 4b = 342 }}}
(1) {{{ -a + b = -47 }}} ( subtract (1) from (2) )
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{{{ 5b = 295 }}}
{{{ b = 59 }}}
and
(1) {{{ a = b + 47 }}}
(1) {{{ a = 59 + 47 }}}
(1) {{{ a = 106 }}}
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106 $5 bills
59 $20 bills
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check:
(2) {{{ 5a + 20b = 1710 }}}
(2) {{{ 5*106 + 20*59 = 1710 }}}
(2) {{{ 530 + 1180 = 1710 }}}
(2) {{{ 1710 = 1710 }}}
OK