3600 - 1/3*(200+400+600) + (0 + 3200)/2 + 1/9*1000 + 1/9*1/9*(3*800+3*600+3*400) + 1/9*1/(9*8)*(6*600+18*400+24*200) + 1/9*1/(9*8*7)*(6*400+54*200)

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