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Multiplying dependent probabilities

A family plans to have three children. It is equally likely that each child will be a boy or a girl. Use the sample space of possible outcomes below to answer each of the following questions.
What is P(A)P(A), the probability that the first child is a girl?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
What is P(B)P(B), the probability that the last two children are boys?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
What is P(A | B)P(A\text{ | }B), the probability that the first child is a girl, given that the last two are boys?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
What is P(B | A)P(B\text{ | }A), the probability that the last two children are boys, given that the first is a girl?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
What is P(A and B)P(A\text{ and }B), the probability that the first child is a girl and the last two are boys?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
What is P(A)P(B | A)P(A)\cdot P(B\text{ | }A)?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
What is P(B)P(A | B)P(B)\cdot P(A\text{ | }B)?
  • Your answer should be
  • an integer, like 66
  • an exact decimal, like 0.750.75
  • a proper fraction, like 1/21/2 or 6/106/10
  • an improper fraction, like 10/710/7 or 14/814/8
  • a mixed number, like 1 3/41\ 3/4
  • a percent, like 12.34%12.34\%
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