Question

In a certain soccer tournament you play 6 games. In every match you get 3 points if you win, 1 point for a draw and 0 points if you lose. For each match the probability you win is 0.5, the probability you draw is 0.1 and the probability you lose is 0.4, independently of the results of all other matches. What is the probability you Önish?

Answer 1

0.430625 = 0.431

Explanation:

Let W represent winning, D represent a draw and L represent a loss.

12+ points can be garnered in each of the following ways.

6W 0D 0L

5W 1D 0L

5W 0D 1L

4W 2D 0L

4W 1D 1L

4W 0D 2L

3W 3D 0L

The probability of getting 12+ points is the sum of all these 7 probabilities.

Knowing that P(W) = 0.5

P(D) = 0.1

P(L) = 0.4

P(6W 0D 0L) = [6!/(6!0!0!)] 0.5⁶ 0.1⁰ 0.4⁰ = 0.015625

P(5W 1D 0L) = [6!/(5!1!0!)] 0.5⁵ 0.1¹ 0.4⁰ = 0.01875

P(5W 0D 1L) = [6!/(5!0!1!)] 0.5⁵ 0.1⁰ 0.4¹ = 0.075

P(4W 2D 0L) = [6!/(4!2!0!)] 0.5⁴ 0.1² 0.4⁰ = 0.09375

P(4W 1D 1L) = [6!/(4!1!1!)] 0.5⁴ 0.1¹ 0.4¹ = 0.075

P(4W 0D 2L) = [6!/(4!0!2!)] 0.5⁴ 0.1⁰ 0.4² = 0.15

P(3W 3D 0L) = [6!/(3!3!0!)] 0.5³ 0.1³ 0.4⁰ = 0.0025

The probability of getting 12+ points = 0.015625 + 0.01875 + 0.075 + 0.09375 + 0.075 + 0.15 + 0.0025 = 0.430625