SOLUTION: 15. There are 20 children in the cast of a class play, and 8 of the
children are boys. Of the boys, 4 have a speaking part in the
play, and of the girls, 8 do not have a speaking
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-> SOLUTION: 15. There are 20 children in the cast of a class play, and 8 of the
children are boys. Of the boys, 4 have a speaking part in the
play, and of the girls, 8 do not have a speaking
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Question 939002: 15. There are 20 children in the cast of a class play, and 8 of the
children are boys. Of the boys, 4 have a speaking part in the
play, and of the girls, 8 do not have a speaking part in the
play. If a child from the cast of the play is chosen at random,
what is the probability that the child has a speaking part? Answer by mathmate(429) (Show Source):
You can put this solution on YOUR website!
It all looks confusing when we try to juggle with all those numbers in the head. The problem can be solved systematically by constructing a contingency table.
role/gender B G total
speaking...... 4 4 8
silent............ 4 8 12
total............. 8 12 20
Probability of a child having a speaking part is therefore
