Answer:
a) σ = 4933,64
b) CI 99% = ( - 5746 ; 7194 )
c) No difference in brands
Step-by-step explanation:
Brand 1:
n₁ = 8
x₁ = 38222
s₁ = 4974
Brand 2:
n₂ = 8
x₂ = 37498
s₂ = 4893
As n₁ = n₂ = 8 Small sample we work with t -student table
degree of freedom df = n₁ + n₂ - 2 df = 8 +8 -2 df = 14
CI = 99 % CI = 0,99
From t-student table we find t(c) = 2,624
CI = ( x₁ - x₂ ) ± t(c) * √σ²/n₁ + σ²/n₂
σ² = [( n₁ - 1 ) *s₁² + ( n₂ - 1 ) * s₂² ] / n₁ +n₂ -2
σ² = 7* (4974)² + 7*( 4893)² / 14
σ² = 24340783 σ = 4933,64
√ σ²/n₁ + σ²/n₂ = √ 24340783/8 + 24340783/8
√ σ²/n₁ + σ²/n₂ = 2466
CI 99% = ( x₁ - x₂ ) ± 2,624* 2466
CI 99% = 724 ± 6470
CI 99% = ( - 5746 ; 7194 )
As we can see CI 99% contains 0 and that means that there is not statistical difference between mean life of the two groups
we know that having similar triangles so the ratio of sides,area and volume are same.

we know that
will be the area of triangle.

so 
so the ratio of the perimeter of two triangles will be

ratio of the perimeter=
9514 1404 393
Answer:
64r -48r -144
Step-by-step explanation:
The January cost expression is ...
62p -48p -144 -432 = profit
The cost is identified as having 3 components, so the profit will have 4 components:
(selling price)×p - ((cost per unit)×p +(fixed monthly cost)) -(first month startup cost) = profit
Comparing this to the given equation, we identify the components as ...
selling price = 62
cost per unit = 48
fixed monthly cost = 144
first month startup cost = 432
We note that 432 = 3×144, so is consistent with the description of startup costs.
Increasing the selling price by $2 will raise it from 62 to 64. In February, the initial month startup cost disappears, so the profit equation becomes ...
(selling price)×r - ((cost per unit)×r +(fixed monthly cost)) = profit
64r -48r -144 = profit
I believe it’s 250 ounces