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fornita2
Mar 27, 2009, 07:19 AM
A kindergarten class consists of 14 boys and 11 girls. If the teacher selects children from the class using random sampling,

a. What is the probability that the first child selected will be a girl?
b. If the teacher selects a random sample of n=3 children and the first two children are both boys, what is the probability tha the third child selected will be a girl?

BRycraft
Mar 27, 2009, 08:04 AM
The Probability for part a is 44% chance as there are 25 kids in the class and 11 are girls so 11/25=.44 or 44%
Part B= 47% almost 48% if you round up. If the 2 boys are set aside and not put back in the total group there are then a total of 23 kids in the class 11 of them still girls, 11/23= .478 nearly 48%