Answer:
μ ≈ 2.33
σ ≈ 1.25
Step-by-step explanation:
Each person has equal probability of ⅓.
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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
Answer:
The area is 72 cm².
Step-by-step explanation:
Since it is equivalent triangle
h = b
so,
b + b + b (since all sides are equal)= 36 cm
3b = 36 cm
or, b = 36/3
so, b = 12 cm
so
area of triangle = (1/2)×b×h
= (1/2)×12cm×12cm
= 6cm × 12cm
= 72 cm²
Answer:
x = 19
Step-by-step explanation:
Vertical angles are equal
So
7x - 8 = 6x + 11
7x - 6x = 11 + 8
x = 19
Answer:
40 points
Step-by-step explanation:
Hello from MrBillDoesMath!
Answer: x = 7/10
Discussion:
To eliminate fractions multiply each side by 10:
10 ( 9/5x - 2/5 ) = 10 * ( 8x +3)/10 or
10 * ( 9/5)x - 10 *(2/5) = 8x + 3 or
9 *2 x - 2*2 = 8x +3 or
18x - 4 = 8x + 3. Subtract 8x for each side:
18x - 8x - 4 = (8x - 8x) + 3 or
10x -4 = 0x + 3 or
10x -4 = 3 or
10x = 7
x = 7/10
Thank you,
MrB
