Question 814273
It took me a few minutes to realize that 
a pecan is not a nut. It's a seed right?
Let {{{ a }}} = pounds of pecan mixture needed
Let {{{ b }}} = pounds of cashew mixture needed
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(1) {{{ a + b = 180 }}}
(2) {{{ ( .33a + .01b ) / 180 = .09 }}}
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(2) {{{ .33a + .01b = .09*180 }}}
(2) {{{ .33a + .01b = 16.2 }}}
(2) {{{ 33a + b = 1620 }}}
and
(1) {{{ b = 180 - a }}}
Substitute (1) into (2)
(2) {{{ 33a + 180 - a = 1620 }}}
(2) {{{ 32a = 1440 }}}
(2) {{{ a = 45 }}}
and, since
(1) {{{ b = 180 - a }}}
(1) {{{ b = 180 - 45 }}}
(1) {{{ b = 135 }}}
135 pounds of cashew mixture are needed, and
the actual pounds of cashews are:
{{{ .01*135 }}} =  1.35 pounds
check:
(2) {{{ ( .33a + .01b ) / 180 = .09 }}}
(2) {{{ ( .33*45 + .01*135 ) / 180 = .09 }}}
(2) {{{ ( 14.85 + 1.35 ) / 180 = .09 }}}
(2) {{{ 16.2 = .09*180 }}}
(2) {{{ 16.2 = 16.2 }}}
OK