Question

A vendor converts the weights on the packages she sends out from pounds to kilograms (1kg approximately equals 2.2 pounds).

Answer 1

Answer:

a) b) the standard deviation and the mean is affected by the conversion factor as well

c)  the mean is displaced by b units

Step-by-step explanation:

for a new variable

Y=a*X  , where a= constant (conversion factor= 1 kg/2.2 pounds)

then

p(y)= p(a*X) = p(X)

a) mean =μ=E(Y)= ∑ a*X*p(y) = a ∑ X*p(x) = a* E(X)

mean =μ=a*μₓ

b) σ² = ∑ (Y-μ)²* p(y) =  ∑ (a*X-a μₓ)²* p(y) = a²*∑ (X-μₓ)²* p(x) = a²*σₓ²

then

standard deviation = σ= √σ²=√(a²*σₓ²) = a*σₓ

standard deviation = σ= a*σₓ

then the standard deviation and the mean is affected by the conversion factor as well

c) nevertheless for a displacement b

Y₂=X + b (b= constant= 50 gr)

p(Y₂)= p(X + b) = p(X)

then

mean =μ=∑ (X-b)*p(y)=∑ X*p(x)- b ∑ p(x) = E(X) -

mean =μ=μₓ - b

then the mean is displaced by b units