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@ @QPS@ @pý†bɾa@ @
120x + 100y = 8000
()

180x + 120y − (120x + 100y) = 0.38 × 8000

( ) 60x + 20y = 3040
( ) −2 ( )

60y = 1920

y = 1920 = 32
60

()

120x + 100(32) = 8000

120x = 8000 − 3200

120x = 4800

. x = 40