In a lottery game, a player picks six numbers from 1 to 30. This means that there are 593775 ways to play the game. If the player gets the 1 combination that matches all six numbers, they win 50,000 dollars. The other 593774 combinations result in losing $1. What is the expected value of this game?

Respuesta :

Given:

Numbers picked from 1 to 30 = 6 numbers

Number of ways = 593775

1 combination = $50,000

Given that the other 593774 combinations result in losing $1, let's find the expected value of losing the game.

Let's first find the number of ways of picking 6 numbers out of 30 numbers.

Apply the combination formula:

[tex]\begin{gathered} ^{30}C_6=\frac{30!}{6!(30-6)!} \\ \\ =\frac{30!}{6!(24)!} \\ \\ =\frac{30*29*28*27*26*25*24!}{6*5*4*3*2*1*24!} \\ \\ =\frac{427518000}{720} \\ \\ =593775\text{ ways} \end{gathered}[/tex]

The probability of winning will be:

[tex]P(win\text{ 50000\rparen = }\frac{1}{593775}[/tex]

The probability of losing is:

[tex]P(lose\text{ 1\rparen = }\frac{593774}{593775}[/tex]

Hence, the expected value will be:

[tex]\begin{gathered} E=50000*\frac{1}{593775}+((-1)*\frac{593774}{593775}) \\ \\ E=50000*\frac{1}{593775}-\frac{593774}{593775} \\ \\ E=\frac{50000}{593775}-\frac{593774}{593775} \end{gathered}[/tex]

Solving further, we have:

[tex]\begin{gathered} E=\frac{50000-593774}{593775} \\ \\ E=-\frac{543774}{593775} \\ \\ E=-0.916 \end{gathered}[/tex]

Therefore, the expected value of this game is -0.916

ANSWER:

-0.916