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Let 40 yuan and 50 yuan each have X, then 30 yuan has (200-2X).

40X+50X+30(200-2X)=780

30X= 1800

X=60

200-2X=80

There are 60 in 50 yuan, 40 yuan and 80 in 30 yuan.

(The income should be 780 yuan, but it can't be 7800 yuan, because all 20 50 yuan tickets are only 1000 yuan. Or there are 200 tickets, then there are 60 tickets in 50 yuan and 80 tickets in 30 yuan.

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