Question 1025027
Let {{{ n }}} = number of nickels
Let {{{ d }}} = number of dimes
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(1) {{{ n + d = 100 }}}
(2) {{{ 5n + 10d = 700 }}} ( in cents )
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(2) {{{ n + 2d = 140 }}}
Subtract (1) from (2)
(2) {{{ n + 2d = 140 }}}
(1) {{{ -n - d = -100 }}}
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{{{ d = 40 }}}
and
(1) {{{ n + d = 100 }}}
(1) {{{ n = 60 }}}
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There are 60 nickels and 40 dimes
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check:
(2) {{{ 5n + 10d = 700 }}}
(2) {{{ 5*60 + 10*40 = 700 }}}
(2) {{{ 300 + 400 = 700 }}}
(2) {{{ 700 = 700 }}}
OK