Do you have an answer? What do you think it is?
Answer:
276 4/7 ft
Step-by-step explanation:
Let r1 represent the radius of the inner circle. Then its circumference in feet is ...
C = 2πr
66 = 2π(r1)
If the radius of the outer circle is (r1 +44), then its circumference is ...
C = 2π(r1 +44) = 2π(r1) +2π(44)
C = 66 +88π
Then the difference in the circumferences is ...
(66 +88π) - (66) = 88π
Using the given value of π, the difference in circumferences is ...
(88 ft)(22/7) = 1936/7 ft = 276 4/7 ft
Answer:
no real answer
Step-by-step explanation:
distribute the -4 and combine all of the like terms on the left side = r-8-4r, then -8-3r
then we have 7-3r=-8-3r
from here, we can already tell that there's no real answer. this is because the two -3r will cancel, leaving no variable.
since 7 doesn't equal -8, there is no answer.
if, for example, the value on both sides of the equal sign were the same after the variable was eliminated, then your answer would be all real numbers
Answer:
Step-by-step explanation:
Hello!
The objective of this experiment is to test if two different foam-expanding agents have the same foam expansion capacity
Sample 1 (aqueous film forming foam)
n₁= 5
X[bar]₁= 4.7
S₁= 0.6
Sample 2 (alcohol-type concentrates )
n₂= 5
X[bar]₂= 6.8
S₂= 0.8
Both variables have a normal distribution and σ₁²= σ₂²= σ²= ?
The statistic to use to make the estimation and the hypothesis test is the t-statistic for independent samples.:
t= ![\frac{(X[bar]_1 - X[bar]_2) - (mu_1 - mu_2)}{Sa*\sqrt{\frac{1}{n_1} + \frac{1}{n_2 } } }](https://tex.z-dn.net/?f=%5Cfrac%7B%28X%5Bbar%5D_1%20-%20X%5Bbar%5D_2%29%20-%20%28mu_1%20-%20mu_2%29%7D%7BSa%2A%5Csqrt%7B%5Cfrac%7B1%7D%7Bn_1%7D%20%2B%20%5Cfrac%7B1%7D%7Bn_2%20%7D%20%7D%20%7D)
a) 95% CI
(X[bar]_1 - X[bar]_2) ±
*
Sa²=
=
= 0.5
Sa= 0.707ç

(4.7-6.9) ± 2.306* 
[-4.78; 0.38]
With a 95% confidence level you expect that the interval [-4.78; 0.38] will contain the population mean of the expansion capacity of both agents.
b.
The hypothesis is:
H₀: μ₁ - μ₂= 0
H₁: μ₁ - μ₂≠ 0
α: 0.05
The interval contains the cero, so the decision is to reject the null hypothesis.
<u>Complete question</u>
a. Find a 95% confidence interval on the difference in mean foam expansion of these two agents.
b. Based on the confidence interval, is there evidence to support the claim that there is no difference in mean foam expansion of these two agents?