Question 971871
Let {{{ b }}} = cost of 1 blouse
Let {{{ t }}} = cost of 1 tie
Let {{{ n }}} = cost of 1 necklace
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(1) {{{ 3b + 2t + n }}} is the total cost of items
(2) {{{ t = 2b }}}
(3) {{{ t = 4n }}}
(4) {{{ t = 45 }}}
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(2) {{{ 45 = 2b }}}
(2) {{{ b = 22.5 }}}
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(3) {{{ 45 = 4n }}}
(3) {{{ n = 11.25 }}}
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(1) {{{ 3b + 2t + n }}} 
(1) {{{ 3*22.5 + 2*45 + 11.25 }}}
(1) {{{ 67.5 + 90 + 11.25 = 168.75 }}}
Total cost is $168.75
You are correct if my math is OK