expected value of the game

[mahi]

can anyone help me with these two math?i don't understand if i need to choose from 26 or 13 (for question 2)

1.You play a game in which you are dealt one card at random from a standard deck of 52 cards. The payoffs are:

• $10 if you get a face card (a jack, a queen, or a king)
• Twice the number showing on a number card: $2 for an ace, $4 for a 2, and so on up to $20 for a 10

What is the expected value of the game?

2.
In a drastically simplified poker game, you are dealt two cards from a standard deck of 52 cards. The payoffs are:

• $50 if you get a pair (two cards of the same denomination)
• $10 if you get a flush (two cards of the same suit)
• What is the expected value of the game?

 

[tkhunny]

You're going to have to show us your work. You can't have nothing to offer, Had you shown your own work in the beginning - in the very first post - you would be getting help right now, rather than a plea for you to demonstrate personal effort.

 

[Steven G]

Since you choosing two cards from a standard deck of 52 cards, I would assume that you are choosing from 52. Where did you get 2 and 26 from?

 

[pka]

can anyone help me with these two math?i don't understand if i need to choose from 26 or 13 (for question 2)
1.You play a game in which you are dealt one card at random from a standard deck of 52 cards. The payoffs are:
$10 if you get a face card (a jack, a queen, or a king)
Twice the number showing on a number card: $2 for an ace, $4 for a 2, and so on up to $20 for a 10
What is the expected value of the game?

2. In a drastically simplified poker game, you are dealt two cards from a standard deck of 52 cards. The payoffs are:
$50 if you get a pair (two cards of the same denomination)
$10 if you get a flush (two cards of the same suit)
What is the expected value of the game?

The expected value is the payoff times the probability of the event.
1) The probability of drawing a face card is \(\displaystyle \dfrac{12}{52}\).

2) The probability of drawing a card of denomination \(\displaystyle D,~1\le D\le 10,\) is \(\displaystyle \dfrac{4}{52}\).

 

[mahi]

You're going to have to show us your work. You can't have nothing to offer, Had you shown your own work in the beginning - in the very first post - you would be getting help right now, rather than a plea for you to demonstrate personal effort.

sorry but how can i show my work ? do I need to post the answer that i got by solving the math ?if so , then i got "3/52*10+1/52*2+1/52*4+…+1/52*20" for the first math and i think its wrong, thats why i post it to see if it match with others..sorry!

 

[tkhunny]

"...how can i show my work ? ..."

SO MANY ask this same question. It is a bad question. Give us SOMETHING to go on.

Anything you have will help you to receive a better and faster response.

 

[Steven G]

sorry but how can i show my work ? do I need to post the answer that i got by solving the math ?if so , then i got "3/52*10+1/52*2+1/52*4+…+1/52*20" for the first math and i think its wrong, thats why i post it to see if it match with others..sorry!

You almost have it, this is why we need to see your work!
For example what is the probability of getting a 3? Note that there are four 3s in the deck!!!