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a+b=540 a-25/100a+b-20/100b=416 a-a/4+b-b/4=416 20a-5a+20b-4b/20=416 15a+16b/20=416 15a+16b=416*20 15a+16b=8320 a+b=540⇔a=540-b 15(540-b)+16b=8320 8100-15b+16b=8320 b=8320-8100 b=220 a+b=540 a+220=540 a=540-220 a=320
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a+b=540 a-25/100a+b-20/100b=416 a-a/4+b-b/4=416 20a-5a+20b-4b/20=416 15a+16b/20=416 15a+16b=416*20 15a+16b=8320 a+b=540⇔a=540-b 15(540-b)+16b=8320 8100-15b+16b=8320 b=8320-8100 b=220 a+b=540 a+220=540 a=540-220 a=320