Can someone please help me with #9

snow_lady [41]

Answer:

7/12

Step-by-step explanation:

To subtract fractions, you must make all of the fractions have a common denominator. We can set both of the denominators as 12. To achieve this, you must multiply both sides of 2/3 by 4. This will change the denominator of the fraction, while keeping the fraction equal to 2/3. Doing this will give us 8/12. Now we can subtract. Since the denominators are the same, we only subtract the numerators. Since 8-1 is 7, our answer is 7/12. The denominator does not change.

3 0

3 years ago

At Clark City Zoo, a zookeeper divides 6 bananas equally among

Anuta_ua [19.1K]

Answer:

6÷3

=2

So each chimpanzee Will get 2 bananas

4 0

3 years ago

In triangle DEF, DK is the angle bisector of angle EDF. If EK=2, FK=5, and DF=10, what is the length of DE?

fiasKO [112]

Answer:

4 units

Step-by-step explanation:

In triangle DEF, DK is the angle bisector of angle EDF.

<u>Angle bisector theorem</u> states that if a ray bisects an angle of a triangle, then it divides the opposite side into segments that are proportional to the other two sides.

Hence,

$\dfrac{DE}{DF}=\dfrac{EK}{KF}$

Thus,

$\dfrac{DE}{10}=\dfrac{2}{5}\\ \\5DE=2\cdot 10\\ \\5DE=20\\ \\DE=4$

6 0

4 years ago

The accounting department analyzes the variance of the weekly unit costs reported by two production departments. A sample of cos

madreJ [45]

Answer:

$F=\frac{s^2_2}{s^2_1}=\frac{5.4}{2.3}=2.348$

$p_v =2*P(F_{15,15}>2.348)=0.109$

And we can use the following excel code to find the p value:"=2*(1-F.DIST(2.348,15,15,TRUE))"

Since the $p_v > \alpha$ we have enough evidence to FAIL to reject the null hypothesis. And we can say that we don't have enough evidence to conclude that the variation is different between the two groups at 10% of significance.

Step-by-step explanation:

Assuming the following question :"The accounting department analyzes the variance of the weekly unit costs reported by two production departments. Asample of 16 cost reports for each of the two departments shows cost variances of 2.3 and 5.4, respectively. Is this sample sufficient to conclude that the two production departments differ in terms of unit cost variance? Use α= .10."

Data given and notation

$n_1 = 16$ represent the sampe size for sample 1

$n_2 =16$ represent the sample size for sample 2

$s^2_1 = 2.3$ represent the sample variance for sample 1

$s^2_2 = 5.4$ represent the sample variance for sample 2

$\alpha=0.1$ represent the significance level provided

Confidence =0.9 or 9%

F test is a statistical test that uses a F Statistic to compare two population variances, with the sample deviations s1 and s2. The F statistic is always positive number since the variance it's always higher than 0. The statistic is given by:

$F=\frac{s^2_2}{s^2_1}$

Solution to the problem

System of hypothesis

We want to test if the variation is equal for both groups or no, so the system of hypothesis are:

H0: $\sigma^2_1 = \sigma^2_2$

H1: $\sigma^2_1 \neq \sigma^2_2$

Calculate the statistic

Now we can calculate the statistic like this:

$F=\frac{s^2_2}{s^2_1}=\frac{5.4}{2.3}=2.348$

Now we can calculate the p value but first we need to calculate the degrees of freedom for the statistic. For the numerator we have $n_2 -1 =16-1=15$ and for the denominator we have $n_1 -1 =16-1=15$ and the F statistic have 15 degrees of freedom for the numerator and 15 for the denominator. And the P value is given by:

P value

Since is a bilateral test the p value is given by

$p_v =2*P(F_{15,15}>2.348)=0.109$

And we can use the following excel code to find the p value:"=2*(1-F.DIST(2.348,15,15,TRUE))"

Conclusion

Since the $p_v > \alpha$ we have enough evidence to FAIL to reject the null hypothesis. And we can say that we don't have enough evidence to conclude that the variation is different between the two groups at 10% of significance.

4 0

4 years ago

Fill in the blank with the missing term in the pattern. 4,-8, 16, ______ 64

MrRissso [65]

Answer:

-32

Step-by-step explanation:

Because if you multiply

4 x-2=-8

-8 x -2=16

16 x -2 =-32

-32 x -2=64

5 0

3 years ago