Answer:
μ ≈ 2.33
σ ≈ 1.25
Step-by-step explanation:
Each person has equal probability of ⅓.
![\left[\begin{array}{cc}X&P(X)\\1&\frac{1}{3}\\2&\frac{1}{3}\\4&\frac{1}{3}\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7DX%26P%28X%29%5C%5C1%26%5Cfrac%7B1%7D%7B3%7D%5C%5C2%26%5Cfrac%7B1%7D%7B3%7D%5C%5C4%26%5Cfrac%7B1%7D%7B3%7D%5Cend%7Barray%7D%5Cright%5D)
The mean is the expected value:
μ = E(X) = ∑ X P(X)
μ = (1) (⅓) + (2) (⅓) + (4) (⅓)
μ = ⁷/₃
The standard deviation is:
σ² = ∑ (X−μ)² P(X)
σ² = (1 − ⁷/₃)² (⅓) + (2 − ⁷/₃)² (⅓) + (4 − ⁷/₃)² (⅓)
σ² = ¹⁴/₉
σ ≈ 1.25
The answer is 3x^3+15x^2-12x.
Answer:
3 triangles
Step-by-step explanation:
Perimeter of triangle = a + b + c
Given that :
P = 12
and a, b, c are natural numbers
Let :
Side A = a
Side B = b
Side C = 12 - (a + b)
Side A + side B > side C - - - (condition 1)
a + b > 12 - (a + b)
a + b > 12 - a - b
a + a + b + b > 12
2a + 2b > 12
2(a + b) > 12
a + b > 6
Side A - side B < side C
a - b < 12 - (a + b)
a - b + a + b < 12
2a < 12
a < 6
b < 6 (arbitrary point)
Going by the Constraint above :
The only three possibilities are :
(2, 5, 5)
(3, 4, 5)
(4, 4, 4)
Total number of triangle = 3
Equilateral triangle (all 3 sides equal) = (4, 4, 4) = 1
Isosceles triangle (only 2 sides equal) = (2, 5, 5) = 1
Answer:
no se podrías resolverlo tu
Answer:
9/10
Step-by-step explanation:
