Answer:
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
