Which is equivalent to (9y^2-4x)(9y^2+4x), and what type of special product is it?

What is 10 time 100000000000

katrin2010 [14]

1,000,000,000,000 is the answer

7 0

3 years ago

What are the domain and range of the function f(x)=sqrt(x-7) +9

GenaCL600 [577]

Domain: x ≥ 7

Range (7,9)

5 0

4 years ago

Read 2 more answers

Men and women (ages 22–40) were surveyed to choose a favorite free-time activity: playing sports, dancing, or watching movies/TV

WITCHER [35]

can you please add the answers to choose from? I'd like to help

4 0

4 years ago

Find the area, correct to the nearest square

Lady bird [3.3K]

Answer:

1269 square meters

Step-by-step explanation:

The path and the plot of land form two concentric circles (they have the same center). The radius of the plot of land is 100m (half of the diameter) and the radius of the larger circle, formed by putting a 2m wide path around the plot of land, is 102m. Thus, the area of the path is $\pi *102^2$ minus $\pi *100^2$ which will be $10404\pi-10000\pi$ which is $404\pi$ . Estimate $\pi$ to 3.141 and calculate, getting 1268.964... which is 1269, rounded to the nearest square meter.

Hope this helps :)

7 0

3 years ago

Engineers at a large automobile manufacturing company are trying to decide whether to purchase brand A or brand B tires for the

andre [41]

Answer:

$s_p =\sqrt{\frac{(12 -1)(5100)^2 +(12-1)(5900)^2}{12 +12 -2}}=5514.526$

$t=\frac{(37900-39800)-0}{5514.526\sqrt{\frac{1}{12}+\frac{1}{12}}}}=-0.844$

$p_v =2*P(t_{22}$

Comparing the p value with a significance level for example $\alpha=0.1$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can conclude that the true means are not significantly different.

Step-by-step explanation:

Data given and notation

$\bar X_{A}=37900$ represent the mean for A

$\bar X_{B}=39800$ represent the mean for B

$s_{A}=5110$ represent the sample standard deviation for A

$s_{B}=5900$ represent the sample standard deviation for B

$n_{A}=12$ sample size for the group A

$n_{B}=12$ sample size for the group B

$\alpha$ Significance level provided

t would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the means are equal or not, the system of hypothesis would be:

Null hypothesis: $\mu_{A}-\mu_{B}= 0$

Alternative hypothesis: $\mu_{A} - \mu_{B}\neq 0$

We don't have the population standard deviation's but we assume that the population deviation is equal for both populations, so we can apply a t test to compare means, and the statistic is given by:

$t=\frac{(\bar X_{A}-\bar X_{B})-\Delta}{s_p\sqrt{\frac{1}{n_{A}}+\frac{1}{n_{B}}}}$ (1)

Where $s_p$ represent the standard deviation pooled given by:

$s_p =\sqrt{\frac{(n_A -1)s^2_A +(n_B -1)s^2_B}{n_A +n_B -2}}$

$s_p =\sqrt{\frac{(12 -1)(5100)^2 +(12-1)(5900)^2}{12 +12 -2}}=5514.526$

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

With the info given we can replace in formula (1) like this:

$t=\frac{(37900-39800)-0}{5514.526\sqrt{\frac{1}{12}+\frac{1}{12}}}}=-0.844$

P value

We need to find first the degrees of freedom given by:

$df=n_A +n_{B}-2=12+12-2=22$

Since is a two tailed test the p value would be:

$p_v =2*P(t_{22}$

Comparing the p value with a significance level for example $\alpha=0.1$ we see that $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can conclude that the true means are not significantly different.

6 0

4 years ago