Question 1055203
Let {{{ n }}} = number of nickels he has
Let {{{ q }}} = number of quarters he has
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(1) {{{ q = 2n }}}
(2) {{{ 5n + 25q = 275 }}}
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(2) {{{ n + 5q = 55 }}}
Plug (1) into (2)
(2) {{{ n + 5*(2n) = 55 }}}
(2) {{{ 11n = 55 }}}
(2) {{{ n = 5 }}}
He has 5 nickels
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check:
(1) {{{ g = 2*5 }}}
(1) {{{ q = 10 }}}
and
(2) {{{ 5*5 + 25q = 275 }}}
(2) {{{ 25 + 25q = 275 }}}
(2) {{{ 25q = 250 }}}
(2) {{{ q = 10 }}}
OK