Answer:
-14w+12
Step-by-step explanation:
10 - 7w - 13 - 7w + 15
Combine like terms
- 7w - 7w + 10-13+15
-14w+12
Since they are intersecting lines, you would equal them to each other.
(5x+4)= (8x-71)
-8x. -8x
-3x + 4 = -71
- 4. -4
-3x = -75
Divide 3x by both sides gets you x = 25
Answer:
Bias for the estimator = -0.56
Mean Square Error for the estimator = 6.6311
Step-by-step explanation:
Given - A normally distributed random variable with mean 4.5 and standard deviation 7.6 is sampled to get two independent values, X1 and X2. The mean is estimated using the formula (3X1 + 4X2)/8.
To find - Determine the bias and the mean squared error for this estimator of the mean.
Proof -
Let us denote
X be a random variable such that X ~ N(mean = 4.5, SD = 7.6)
Now,
An estimate of mean, μ is suggested as

Now
Bias for the estimator = E(μ bar) - μ
= 
= 
= 
= 
= 
= 3.9375 - 4.5
= - 0.5625 ≈ -0.56
∴ we get
Bias for the estimator = -0.56
Now,
Mean Square Error for the estimator = E[(μ bar - μ)²]
= Var(μ bar) + [Bias(μ bar, μ)]²
= 
= 
= ![\frac{1}{64} ( [{3Var(X_{1}) + 4Var(X_{2})] }) + 0.3136](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B64%7D%20%28%20%5B%7B3Var%28X_%7B1%7D%29%20%2B%204Var%28X_%7B2%7D%29%5D%20%20%7D%29%20%2B%200.3136)
= ![\frac{1}{64} [{3(57.76) + 4(57.76)}] } + 0.3136](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B64%7D%20%5B%7B3%2857.76%29%20%2B%204%2857.76%29%7D%5D%20%20%7D%20%2B%200.3136)
= ![\frac{1}{64} [7(57.76)}] } + 0.3136](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B64%7D%20%5B7%2857.76%29%7D%5D%20%20%7D%20%2B%200.3136)
= ![\frac{1}{64} [404.32] } + 0.3136](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B64%7D%20%5B404.32%5D%20%20%7D%20%2B%200.3136)
= 
= 6.6311
∴ we get
Mean Square Error for the estimator = 6.6311
Answer:
13° , 29° , 138°
Step-by-step explanation:
let x be the smallest angle , then
2x + 3 is the middle angle and
2x + 3 + 109 is the largest angle
summing the 3 angles and equating to 180
x + 2x + 3 + 2x + 3 + 109 = 180 , that is
5x + 115 = 180 ( subtract 115 from 180 )
5x = 65 ( divide both sides by 5
x = 13
2x + 3 = 2(13) + 3 = 26 + 3 = 29
2x + 3 + 109 = 29 + 109 = 138
the 3 angles are 13° , 29° , 138°
Answer:
c. 3680
Step-by-step explanation:
In 2010, the population was 8000.
In 2014, it increased by 15%.
Population in 2014 :
= 8000 + 15/100×8000
= 8000 + 1200
= 9200.
Now, 2/5 of the population was age 12 or under.
= 2/5 × 9200
= 2×1840
= 3680
Answer - c) 3680