Question:
A poorly-run restaurant messes up one order in three. You and two people from work each eat there
once this month, each of you eating there on a different day. What is the probability that this month the
restaurant didn’t mess up any of the orders placed by your or your two friends? (Your answer should be a
fraction. Assume independence.)

Question

Question: 
A poorly-run restaurant messes up one order in three. You and two people from work each eat there
once this month, each of you eating there on a different day. What is the probability that this month the
restaurant didn’t mess up any of the orders placed by your or your two friends? (Your answer should be a
fraction. Assume independence.)

mathmale · Answer

Think of the problem this way:  P(messed up order) = 1/3
P(order not messed up) = 1 - 1/3 = 2/3

that's for one person on one day.

Using this info, how would you address this question?  What is the joint probability of independent events?

mathmale · Answer

suppose A and B  are independent events, and P(A) and P(B) are known.  What is the probability that these events will occur simultaneously?  "Joint probability."