Question 1060573
(1) {{{ p + n = 10 }}}
(2) {{{ .55p + .85n = 6.7 }}}
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(2) {{{ 55p + 85n = 670 }}}
(2) {{{ 11p + 17n = 134 }}}
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Multiply both sides of (1) by {{{ 11 }}}
and subtract (1) from (2)
(2) {{{ 11p + 17n = 134 }}}
(1) {{{ -11p - 11n = -110 }}}
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{{{ 6n = 24 }}}
{{{ n = 4 }}}
and
(1) {{{ p + n = 10 }}}
(1) {{{ p = 6 }}}