Amy was born on a Tuesday. What is the probability that exactly two of her three best friends were also born on Tuesday? Express your answer as a common fraction.
+23254 Call her friends B, C, and D.
The probability that one is born on a Tuesday is (1/7).
The probability that one isn't born on a Tuesday is (6/7).
If B and C are born on a Tuesday and D isn't: (1/7)x(1/7)x(6/7) =
If B and D are born on a Tuesday and C isn't: (1/7)x(6/7)x(1/7) =
If C and D are born on a Tuesday and B isn't: (6/7)x(1/7)x(1/7) =
Calculate the three answers above and add them together for the total probability ...
+23254 Call her friends B, C, and D.
The probability that one is born on a Tuesday is (1/7).
The probability that one isn't born on a Tuesday is (6/7).
If B and C are born on a Tuesday and D isn't: (1/7)x(1/7)x(6/7) =
If B and D are born on a Tuesday and C isn't: (1/7)x(6/7)x(1/7) =
If C and D are born on a Tuesday and B isn't: (6/7)x(1/7)x(1/7) =
Calculate the three answers above and add them together for the total probability ...
