Help math 3 and 5 please.

Point A is located at (5, 10) and point B is located at (20, 25).

Alla [95]

Let's say the point is C, so C partitions AB into two pieces, where AC is at a ratio of 3 and CB is at a ratio of 7, thus 3:7,

$\bf \left. \qquad \right.\textit{internal division of a line segment}
\\\\\\
A(5,10)\qquad B(20,25)\qquad
\qquad 3:7
\\\\\\
\cfrac{AC}{CB} = \cfrac{3}{7}\implies \cfrac{A}{B} = \cfrac{3}{7}\implies 7A=3B\implies 7(5,10)=3(20,25)\\\\
-------------------------------\\\\
{ C=\left(\cfrac{\textit{sum of "x" values}}{\textit{sum of ratios}}\quad ,\quad \cfrac{\textit{sum of "y" values}}{\textit{sum of ratios}}\right)}\\\
-------------------------------$

$\bf C=\left(\cfrac{(7\cdot 5)+(3\cdot 20)}{3+7}\quad ,\quad \cfrac{(7\cdot 10)+(3\cdot 25)}{3+7}\right)
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C=\left( \cfrac{35+60}{10}~~,~~\cfrac{70+75}{10} \right)\implies C=\left(\cfrac{95}{10}~~,~~\cfrac{145}{10} \right)
\\\\\\
C=\left( \cfrac{19}{2}~~,~~\cfrac{29}{2} \right)\implies C=\left( 9\frac{1}{2}~~,~~14\frac{1}{2} \right)$

8 0

3 years ago

I am a solid figure with two congruent polygons that are bases connected with lateral faces that are rectangles

Andrews [41]

We have lateral faces that are rectangles and 2 congruent polygons that are bases. This must be 3-dimensional solid figure - quadrilateral prism. If those 2 bases are squares then it is a rectangular prism, but the bases also can be 2 rhombuses. Answer: Quadrilateral prism.

5 0

3 years ago

Maths- please help me with this Q

Reika [66]

Step-by-step explanation:

please mark me as brainlest

5 0

2 years ago

Read 2 more answers

125^2x = 25 Help me please

Andrew [12]

Answer: 23

Step-by-step explanation:

4 0

3 years ago

Read 2 more answers

After once again losing a football game to the college'ss arch rival, the alumni association conducted a survey to see if alumni

antoniya [11.8K]

Answer:

a) The 90% confidence interval would be given (0.561;0.719).

b) $p_v =P(z>2.8)=1-P(z$

c) Using the significance level assumed $\alpha=0.01$ we see that $p_v$ so we have enough evidence at this significance level to reject the null hypothesis. And on this case makes sense the claim that the proportion is higher than 0.5 or 50%.

Step-by-step explanation:

1) Data given and notation

n=100 represent the random sample taken

X=64 represent were in favor of firing the coach

$\hat p=\frac{64}{100}=0.64$ estimated proportion for were in favor of firing the coach

$p_o=0.5$ is the value that we want to test since the problem says majority

$\alpha$ represent the significance level (no given, but is assumed)

z would represent the statistic (variable of interest)

$p_v$ represent the p value (variable of interest)

p= population proportion of Americans for were in favor of firing the coach

Part a

The confidence interval would be given by this formula

$\hat p \pm z_{\alpha/2} \sqrt{\frac{\hat p(1-\hat p)}{n}}$

For the 90% confidence interval the value of $\alpha=1-0.9=0.1$ and $\alpha/2=0.05$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=1.64$

And replacing into the confidence interval formula we got:

$0.64 - 1.64 \sqrt{\frac{0.64(1-0.64)}{100}}=0.561$

$0.64 + 1.64 \sqrt{\frac{0.64(1-0.64)}{100}}=0.719$

And the 90% confidence interval would be given (0.561;0.719).

Part b

We need to conduct a hypothesis in order to test the claim that the proportion exceeds 50%(Majority). :

Null Hypothesis: $p \leq 0.5$

Alternative Hypothesis: $p >0.5$

We assume that the proportion follows a normal distribution.

This is a one tail upper test for the proportion of union membership.

The One-Sample Proportion Test is "used to assess whether a population proportion $\hat p$ is significantly (different,higher or less) from a hypothesized value $p_o$ ".

Check for the assumptions that he sample must satisfy in order to apply the test

a)The random sample needs to be representative: On this case the problem no mention about it but we can assume it.

b) The sample needs to be large enough

$np_o =100*0.64=64>10$

$n(1-p_o)=100*(1-0.64)=36>10$

Calculate the statistic

The statistic is calculated with the following formula:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o(1-p_o)}{n}}}$

On this case the value of $p_o=0.5$ is the value that we are testing and n = 100.

$z=\frac{0.64 -0.5}{\sqrt{\frac{0.5(1-0.5)}{100}}}=2.8$

The p value for the test would be:

$p_v =P(z>2.8)=1-P(z$

Part c

Using the significance level assumed $\alpha=0.01$ we see that $p_v$ so we have enough evidence at this significance level to reject the null hypothesis. And on this case makes sense the claim that the proportion is higher than 0.5 or 50%.

6 0

3 years ago