SOLUTION: Ms.Thomson's class consists of 12 girls and 13 boys. They all put their names in a hat and the teahcer was going to randomly choose two different students to be assistant teachers

Question 66782: Ms.Thomson's class consists of 12 girls and 13 boys. They all put their names in a hat and the teahcer was going to randomly choose two different students to be assistant teachers for the week. What is the probability that it will be a boy and a girl?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Ms.Thomson's class consists of 12 girls and 13 boys. They all put their names in a hat and the teahcer was going to randomly choose two different students to be assistant teachers for the week. What is the probability that it will be a boy and a girl?
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Total # of pairs of students is 25C2=300
Total # of pairs of boys is 13C2=78
Total # of pairs of girls is 12C2=66
Therefore # of boy-girl pairs is 300-78-66=156
So, Prob(goy-girl pair being selected)=156/300
Cheers,
Stan H.
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