Consider the following scenario when answering the following questions:
Imagine a game show on television where one lucky contestant is presented with four upside-down buckets that are numbered 1, 2, 3, and 4. Under one of the buckets is a $100 bill. Under each of the other three buckets is a $10 bill. After the game ends, the contestant will receive the amount of money that is under his or her bucket.
The host of the game show asks the contestant to choose one of the four buckets. After the contestant makes a choice, the host lifts one of the remaining three buckets to reveal a $10 bill under it. At this point, three buckets remain uncovered: the bucket that the contestant originally chose and the two buckets that were not uncovered by the host.
The host subsequently asks the contestant if he or she would like to keep the original bucket or change buckets to one of the two other buckets remaining.

If the contestant changes buckets from the original bucket to one of the other buckets remaining, what is the expected value of the game?

Want to confirm my answer of $40. Thank you.