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3 years ago

Can someone pls help me!!!

Mathematics

1 answer:

max2010maxim [7]3 years ago

4 0

Answer:

It will equally 2 because you need to change the 3 into a 9 because you can't add fractions without having the same common demometer

Step-by-step explanation:

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Please help. I need it now. Thank you!

exis [7]

I don't know these types of questions sorry

8 0

3 years ago

A group of men and women were asked what their favorite pet was, and the results of the survey were tabulated.Petey is consideri

malfutka [58]

You question is of two parts.
For the first part:
<span>A group of men and women were asked what their favorite pet was, and the results of the survey were tabulated.

$\begin{center}
\begin{tabular}
{|c|c|c|c|c|}
 & Cats & Dogs & Other & Total \\ [1ex]
Male & 42 & 58 & 6 & 106 \\
Female & 52 & 48 & 2 & 102 \\ [1ex]
Total & 94 & 106 & 8 & 208
\end{tabular}
\end{center}$

</span>Let event A be defined as randomly choosing someone who picked cats or dogs as their favorite pet. Let event B be defined as a randomly chosen person being male.
Find P(B| NOT A).

P(A) = P(choosing cat) + P(choosing dog) = $\frac{94}{208} + \frac{106}{208} = \frac{200}{208} = \frac{25}{26}$
P(NOT A) = $1- \frac{25}{26} = \frac{1}{26}$
P(B and NOT A) = P(males that did not choose cat or dog) = $\frac{6}{208} = \frac{3}{104}$

P(B | NOT A) = $\frac{P(B \, and \, NOT \, A)}{P(NOT \, A)} = \frac{ \frac{3}{104} }{ \frac{1}{26} } =\frac{3}{104}\times26= \frac{3}{4}$

For the second part of the question.
<span>Petey is considering investing $19 in a certain company. Financial advisors forecast that there is a 30% chance that the stock will increase in value by 10%, and a 70% chance he will lose his initial investment. Determine if Petey should make the investment, and find the expected value of the investment.

If his investment increases by 10%, the value of the investment will be 1.1 x $19 = $20.90 with a probability of 30% or 0.3

The expected value of the investment is given by
$\$20.90\times0.3+(-\$19\times0.7)=\$6.27-\$13.30=-\$7.03$

Therefore, Petey should not make the investment as there is an expectation of a loss from the investment.
</span>

7 0

3 years ago

Help me PLSSSSSSSSSSS

nadezda [96]

Answer:

8. Because if you add the degree of angle 7 to angle 8, then it makes a 180 degree angle, which is supplementary. Hope this helped

4 0

3 years ago

In a recent year, the ACT scores for the math portion of the test were normally distributed, with a mean of 21.1 and a standard

Natali5045456 [20]

Answer:

a) $P(X$

And we can find this probability using the normal standard table or excel:

$P(z$

b) $P(19$

And we can find this probability with this difference:

$P(-0.396$

And in order to find these probabilities we can use tables for the normal standard distribution, excel or a calculator.

$P(-0.396$

c) $P(X>26)=P(\frac{X-\mu}{\sigma}>\frac{26-\mu}{\sigma})=P(Z>\frac{26-21.1}{5.3})=P(z>0.925)$

And we can find this probability using the complement rule and the normal standard table or excel:

$P(z>0.925)=1- P(Z$

d) We can consider unusual events values above or below 2 deviations from the mean

$Lower = \mu -2*\sigma = 21.1 -2*5.3 =10.5$

A value below 10.5 can be consider as unusual

$Upper = \mu +2*\sigma = 21.1 +2*5.3 =31.7$

A value abovr 31.7 can be consider as unusual

Step-by-step explanation:

Previous concepts

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Part a

Let X the random variable that represent the scores of a population, and for this case we know the distribution for X is given by:

$X \sim N(21.1,5.3)$