Question 617840
Let {{{ p }}} = number of pennies
Let {{{ n }}} = number of nickels
given:
(1) {{{ p + n = 450 }}}
(2) {{{  1*p + 5*n = 1450 }}} ( in cents)
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Subtract (1) from (2)
(2) {{{  1*p + 5*n = 1450 }}}
(1) {{{ -p - n = -450 }}}
{{{ 4n = 1000 }}}
{{{ n = 250 }}}
and, since
(1) {{{ p + n = 450 }}}
(1) {{{ p + 250 = 450 }}}
(1) {{{ p = 200 }}}
200 pennies
250 nickels