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The first team (boy,girl) can be arranged in 10*12 = 120 ways.
After that, the second team (boy,girl) can be arranged in 9*11 = 99 ways.
Such teams can be combined in = 60*99 = 5940 different ways for a game. ANSWER
Solved.
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This problem was just posted and solved at this forum approximately a week ago under this link
https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1168171.html
https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1168171.html
I don't like when the problem solved once comes again and again.