(pts) What are the next three numbers in the pattern: 2, -4, 6, -8, 10. <br> Thanks!

A communications tower is supported by two wires, connected at the same point on the ground. One is attached to the tower at D a

viktelen [127]

Answer:

10.99 m

Step-by-step explanation:

✍️What we are basically asked to solve here is to find the distance between C and D.

To find CD, find the length of BC, and BD. Their difference will give us CD.

Thus, BC - BD = CD.

✍️Finding BC using trigonometric ratio formula:

$\theta = 30 + 10 = 40$

Opposite side = BC = ??

Adjacent side = 42 m

Thus:

$tan(\theta) = \frac{opposite}{adjacent}$

Plug in the values

$tan(40) = \frac{BC}{42}$

Multiply both sides by 42

$tan(40) \times 42 = \frac{BC}{42} \times 42$

$35.24 = BC$

BC = 35.24 m

✍️Finding BD using trigonometric ratio formula:

$\theta = 30$

Opposite side = BD = ??

Adjacent side = 42 m

Thus:

$tan(\theta) = \frac{opposite}{adjacent}$

Plug in the values

$tan(30) = \frac{BD}{42}$

Multiply both sides by 42

$tan(30) \times 42 = \frac{BD}{42} \times 42$

$24.25 = BD$

BD = 24.25 m

✍️How much below the top of the tower is the shorter one attached:

Thus,

BC - BD = CD

35.24 m - 24.25 m = 10.99 m

7 0

3 years ago

A medical researcher wondered if there is a significant difference between the mean birth weight of boy and girl babies. Random

Yuliya22 [10]

Answer:

b) independent samples t-test

$t=\frac{(5.92 -5.74)-(0)}{\sqrt{\frac{1.88^2}{5}}+\frac{1.81^2}{5}}=0.154$

$p_v =2*P(t_{8}>0.154) =0.881$

So with the p value obtained and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the mean of the group 1 (boys) is NOT significantly different than the mean for the group 2 (Girls).

Step-by-step explanation:

The system of hypothesis on this case are:

Null hypothesis: $\mu_1 = \mu_2$

Alternative hypothesis: $\mu_1 \neq \mu_2$

Or equivalently:

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

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

Our notation on this case :

$n_1 =5$ represent the sample size for group 1

$n_2 =5$ represent the sample size for group 2

We can calculate the mean and deviation for eaach group with the following formulas:

$\bar X= \frac{\sum_{i=1}^n X_i}{n}$

$s = \sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X_1 =5.92$ represent the sample mean for the group 1

$\bar X_2 =5.74$ represent the sample mean for the group 2

$s_1=1.88$ represent the sample standard deviation for group 1

$s_2=1.81$ represent the sample standard deviation for group 2

If we see the alternative hypothesis we see that we are conducting a bilateral test and with independnet samples t test.

b) independent samples t-test

The statistic is given by this formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{\sqrt{\frac{s^2_1}{n_1}}+\frac{S^2_2}{n_2}}$

And now we can calculate the statistic:

$t=\frac{(5.92 -5.74)-(0)}{\sqrt{\frac{1.88^2}{5}}+\frac{1.81^2}{5}}=0.154$

The degrees of freedom are given by:

$df=5+5-2=8$

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

$p_v =2*P(t_{8}>0.154) =0.881$

So with the p value obtained and using the significance level given $\alpha=0.05$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the mean of the group 1 (boys) is NOT significantly different than the mean for the group 2 (Girls).

7 0

3 years ago

Find the equation of the line which passes through the point (-4,12) and is perpendicular to the given line. Express your answer

Vika [28.1K]

Answer:

y = 1/7x + 88/7

Step-by-step explanation:

y = mx +b

since it is perpendicular you have to get the negative reciprocal of the slope which is 1/7

y = 1/7x + b then you would plug in your points

12 = 1/7(-4) + b and then solve for b

12 = -4/7 + b