I think its the last one, Aidan can expect to save about $27.52 each week. Hope I was correct
I need more information to answer this question, so nobody can answer...
You will have a better chance of winning because your chance before you opened the first door was 1/3 (since there was 3 doors) but now, you have 2 doors left, so it is a 50% chance that you will win.
There are 3 sides. If you draw out a triangle, each line is a separate side (a line segment connecting 2 vertices, or points). You can also see in the word "triangle" the prefix "tri-", meaning "three". It refers to the shape having 3 angles, but when there are 3 angles there are 3 sides to make it up. This is true for other shapes too - in a square, there are 4 sides connecting 4 points, and between each side is an angle, creating 4 angles.