Answer:
Step-by-step explanation:
Let the edge of the cube be a .
Given
Volume V = a³
![\frac{dV}{dt} = 3a^ 2\frac{da}{dt}](https://tex.z-dn.net/?f=%5Cfrac%7BdV%7D%7Bdt%7D%20%3D%203a%5E%202%5Cfrac%7Bda%7D%7Bdt%7D)
= 3a² x 2
= 6a²
If a = 40 cm
![\frac{dV}{dt} = 6 \times 40\times40](https://tex.z-dn.net/?f=%5Cfrac%7BdV%7D%7Bdt%7D%20%3D%206%20%5Ctimes%2040%5Ctimes40)
= 9600 cm³/s .
Didn't know if this was a question but if yes it is
Double the side and subtract by 360
Answer:
Step-by-step explanation:
Hello!
You have two populations of interest and want to compare them. If you define the study variables as:
X₁: average hourly wages of an employee of the Downtown store.
n₁= 25
X[bar]₁= $9
S₁= $2
X₂: average hourly wages of an employee of the North Mall store.
n₂= 20
X[bar]₂= $8
S₂= $1
Both samples taken are independent, assuming that both populations are normal and that their population variances are equal I'll use the Student's-t statistic with a pooled sample variance to calculate the Confidence interval:
95% CI for μ₁ - μ₂
(X[bar]₁-X[bar]₂) ± ![t_{n_1+n_2-2; 1-\alpha /2} * (Sa*\sqrt{\frac{1}{n_1} +\frac{1}{n_2} } )](https://tex.z-dn.net/?f=t_%7Bn_1%2Bn_2-2%3B%201-%5Calpha%20%2F2%7D%20%2A%20%28Sa%2A%5Csqrt%7B%5Cfrac%7B1%7D%7Bn_1%7D%20%2B%5Cfrac%7B1%7D%7Bn_2%7D%20%7D%20%29)
![Sa^2= \frac{(n_1-1)S_1^2+(n_2-1)S_2^2}{n_1+n_2-2}](https://tex.z-dn.net/?f=Sa%5E2%3D%20%5Cfrac%7B%28n_1-1%29S_1%5E2%2B%28n_2-1%29S_2%5E2%7D%7Bn_1%2Bn_2-2%7D)
![Sa^2= \frac{24*4+19*1}{25+20-2}= 2.67](https://tex.z-dn.net/?f=Sa%5E2%3D%20%5Cfrac%7B24%2A4%2B19%2A1%7D%7B25%2B20-2%7D%3D%202.67)
Sa= 1.64
![t_{n_1-n_2-2;1-\alpha /2} = t_{43; 0.975} = 2.017](https://tex.z-dn.net/?f=t_%7Bn_1-n_2-2%3B1-%5Calpha%20%2F2%7D%20%3D%20t_%7B43%3B%200.975%7D%20%3D%202.017)
(9-8)±2.017*![(1.64*\sqrt{\frac{1}{25} +\frac{1}{20} } )](https://tex.z-dn.net/?f=%281.64%2A%5Csqrt%7B%5Cfrac%7B1%7D%7B25%7D%20%2B%5Cfrac%7B1%7D%7B20%7D%20%7D%20%29)
[0.007636;1.9923]
I hope it helps!