Math Riddles?

Question

1. A family has two children. One of them is a boy. What is the probability the other one is a girl?

2. You are in a game show and are asked to choose one of three doors. Behind one of these doors is the prize. Let's call these doors A, B, and C. Assume you chose door A. The host then opens door B to reveal it does not have the prize. You now have the option of sticking with door A or changing to door C. Is there an advantage to either one or is it a 50/50 chance with both?

Hints:

(1) 50/50 is *not* the correct answer to either riddle.

(2) In response to the heriditary answer, assume that any birth has a 50/50 chance of being a boy or a girl (no, this does not contradict the above hint).

Answer 1

50-50 for both.

Answer 2

1. 1/2 ie 50/50

2. it's a 50/50 chance, the probability is 1/2

=)

Answer 3

there's two of them..so i'm sure the other one is a girl..100%
50/50 with both

Answer 4

1. 50/50
2. 50/50...no advantage

Answer 5

you have a 50% chance on both questions...and I thought this was going to be a hard one...

Answer 6

the simple anwer should be 50/50 for both quiestions.

Answer 7

1. more likely to be a boy (its hereditary)
2. you should switch to the other door aka door C!!!!!