In a certain soccer tournament you are playing once with each of the other nine teams. 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 0.2 and the probability you lose is 0.3, independently of the results of all other matches. What is the probability you finish the tournament with at least 20 points

0.430625=0.431

Step-by-step explanation:

0.430625 = 0.431

Step-by-step 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

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step-by-step explanation:

1. practice, practice & more practice

2. review errors

3. master the key concepts

do not try to memorise the processes.

4. understand your doubts.

5. create a distraction free study environment

6. create a mathematical dictionary

7. apply maths to real world problems.