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3 years ago

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The sum of three numbers is 74 the first number is 6 less than the second the third number is 2 times the second what are the nu

mbers

1 answer:

krok68 [10]3 years ago

5 0

Answer:

your answer will be 37 or 3

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A function is given by the equation h (x)=x 2 squared +6x-3. what is h (3)?

Leno4ka [110]

Your "<span>h (x)=x 2 squared +6x-3" is ambiguous. If you meant "x squared," then you need only write x^2 OR "x squared," but NOT "x 2 squared."

I will assume that by "</span><span>h (x)=x 2 squared +6x-3" you actually meant:

</span><span>h(x)=x^2 +6x-3. To find h(3), subst. 3 for x: h(3) = (3)^2 + 6(3) - 3, or

h(3) = 9 + 18 - 3, or h(3) = 24.</span>

5 0

3 years ago

Jessica used 2/3 yard of fabric to make a scarf. Can she make 2 of these scarves with

mr Goodwill [35]

Yes because
1 3/4 is 7/2 and 2/3+2/3=4/3

So yes he can
Hope this helps :-P

5 0

3 years ago

Read 2 more answers

Can someone pls help me with this plsss

tino4ka555 [31]

Answer: D: 242m³

Step-by-step explanation:

Well, 9x5=45 and if you calculate that in cubic meters i believe it would be 243m³ (I'm in 7th grade...=/) HAPPY EARLY VALENTINES DAY! HOPE YOU GET THIS RIGHT! =D

6 0

3 years ago

Read 2 more answers

Two catalysts may be used in a batch chemical process. Twelve batches were prepared using catalyst 1, resulting in an average yi

aalyn [17]

Answer:

a) $t=\frac{(91-85)-(0)}{2.490\sqrt{\frac{1}{12}}+\frac{1}{15}}=6.222$

$df=12+15-2=25$

$p_v =P(t_{25}>6.222) =8.26x10^{-7}$

So with the p value obtained and using the significance level given $\alpha=0.01$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis.

b) $(91-85) -2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =3.309$

$(91-85) +2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =8.691$

Step-by-step explanation:

Notation and hypothesis

When we have two independent samples from two normal distributions with equal variances we are assuming that

$\sigma^2_1 =\sigma^2_2 =\sigma^2$

And the statistic is given by this formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{S_p\sqrt{\frac{1}{n_1}}+\frac{1}{n_2}}$

Where t follows a t distribution with $n_1+n_2 -2$ degrees of freedom and the pooled variance $S^2_p$ is given by this formula:

$\S^2_p =\frac{(n_1-1)S^2_1 +(n_2 -1)S^2_2}{n_1 +n_2 -2}$

This last one is an unbiased estimator of the common variance $\sigma^2$

Part a

The system of hypothesis on this case are:

Null hypothesis: $\mu_2 \leq \mu_1$

Alternative hypothesis: $\mu_2 > \mu_1$

Or equivalently:

Null hypothesis: $\mu_2 - \mu_1 \leq 0$

Alternative hypothesis: $\mu_2 -\mu_1 > 0$

Our notation on this case :

$n_1 =12$ represent the sample size for group 1

$n_2 =15$ represent the sample size for group 2

$\bar X_1 =85$ represent the sample mean for the group 1

$\bar X_2 =91$ represent the sample mean for the group 2

$s_1=3$ represent the sample standard deviation for group 1

$s_2=2$ represent the sample standard deviation for group 2

First we can begin finding the pooled variance:

$\S^2_p =\frac{(12-1)(3)^2 +(15 -1)(2)^2}{12 +15 -2}=6.2$

And the deviation would be just the square root of the variance:

$S_p=2.490$

Calculate the statistic

And now we can calculate the statistic:

$t=\frac{(91-85)-(0)}{2.490\sqrt{\frac{1}{12}}+\frac{1}{15}}=6.222$

Now we can calculate the degrees of freedom given by:

$df=12+15-2=25$

Calculate the p value

And now we can calculate the p value using the altenative hypothesis:

$p_v =P(t_{25}>6.222) =8.26x10^{-7}$

Conclusion

So with the p value obtained and using the significance level given $\alpha=0.01$ we have $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis.

Part b

For this case the confidence interval is given by:

$(\bar X_1 -\bar X_2) \pm t_{\alpha/2} S_p \sqrt{\frac{1}{n_1} +\frac{1}{n_2}}$

For the 99% of confidence we have $\alpha=1-0.99 = 0.01$ and $\alpha/2 =0.005$ and the critical value with 25 degrees of freedom on the t distribution is $t_{\alpha/2}= 2.79$

And replacing we got:

$(91-85) -2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =3.309$

$(91-85) +2.79 *2.490 \sqrt{\frac{1}{12} +\frac{1}{15}} =8.691$

7 0

3 years ago

Susan's elevation at the top of a mountain is 1,530 meters. After 4 hours of climbing down her elevation is 680 meters. What is

Nitella [24]

Answer:

C) -212.5

Step-by-step explanation:

I've done this question on a quiz before.

Hope I helped!! :D

4 0

3 years ago