Question

2. Barbara has a jar of coins, some Canadian, some U.S., and similarly, some quarters, some dimes. [There is no other nationality of coin, nor any other value of coin.] 70% are Canadian coins. Given that it is a Canadian coin, there is a 40% chance it is a quarter. Given that it is not a Canadian coin, there is a 40% chance it is a quarter. Are nationality and value independent? Or is impossible to tell? Please explain how you know.

3. Ian, like Barbara, has a jar of coins, some Canadian, some U.S., and similarly, some quarters, some dimes. [There is no other nationality of coin, nor any other value of coin.] 60% are Canadian; 50% are quarters; and 80% of all quarters are Canadian. What is the probability of picking a coin and it being either Canadian or a quarter?

4. Let’s use the data from Question 9. [60% are Canadian; 50% are quarters; and 80% of all quarters are Canadian.] What’s the probability of it being a Canadian dime?

Answer 1