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2 years ago

5

There are 11 students participating in a spelling bee. in how many ways can the students who go first¸ second¸ and third in the

bee be chosen

1 answer:

Valentin [98]2 years ago

6 0

Three ways because it alternates. 1st, 2nd and 3rd.

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In studying the insurance preferences of homeowners the following conclusions are made: A homeowner is three times as likely to

Ede4ka [16]

Answer:

0.632

Step-by-step explanation:

Given that a homeowner is three times as likely to purchase additional jewelry coverage as additional electronics coverage

If probability of purchasing additional electronics coverage = p, then prob of purchasing jewelry coverage = 3p

The two events are independent hence joint probability is product of these two.

i.e. P(both) = $p(3p) =3p^2$

This is given as 0.2

$3p^2 =0.2\\p = 0.258$

the probability that a homeowner purchases exactly one coverage.

$=P(AUB)-P(A \bigcap B)$

= Prob he purchases I + prob he purchases II-2(prob he purchases both)

$= 0.258+3(0.258)-2(0.2)\\=0.632$

5 0

2 years ago

SAT Writing scores are normally distributed with a mean of 491 and a standard deviation of 113.A university plans to send letter

Sholpan [36]

Answer:

$z=1.405$

And if we solve for a we got

$a=491 +1.405*113=649.765$

So the value of height that separates the bottom 92% of data from the top 8% is 649.765.

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".

Solution to the problem

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:

$X \sim N(491,113)$

Where $\mu=491$ and $\sigma=113$

For this part we want to find a value a, such that we satisfy this condition:

$P(X>a)=0.08$ (a)

$P(X$ (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.92 of the area on the left and 0.08 of the area on the right it's z=1.405. On this case P(Z<1.405)=0.92 and P(z>0.92)=0.08

If we use condition (b) from previous we have this:

$P(X$

$P(z$

But we know which value of z satisfy the previous equation so then we can do this:

$z=1.405$

And if we solve for a we got

$a=491 +1.405*113=649.765$

So the value of height that separates the bottom 92% of data from the top 8% is 649.765.

6 0

2 years ago

Ben says 7 9/100 must be less than 7. 2/10 because 9 hundredths is less than 2 tenths. Do you agree? Draw a line to support your

Marrrta [24]

Yes, I cannot draw a line because this is online. Sorry

5 0

2 years ago

The tables show the relationships between x and y for two data sets. Data Set Data Set I X 5.5 1 Z 11.0 2 10 5 165 3 15 220 2D 5

notka56 [123]

Answer:

C I beleive the answer is C Both data sets show multiplicative relationships.

In Data Set I, y is 5.5 times x, and in Data Set II, y is 5 times x.

Step-by-step explanation:

I beleive the answer it C thank you bye bye have a nice day hope this helped

5 0

1 year ago

Read 2 more answers

Find the inverse of the function. y = 2x2 –4

Alex73 [517]

Answer:

The inverse function is $y=\sqrt{\frac{x+4}{2}}$

Step-by-step explanation:

The given function is $y=2x^2-4$ .

This function is only invertible on the interval, $x\ge 0$ .

To find the inverse on this interval, we interchange $x$ and $y$ .

$x=2y^2-4$

We now make $y$ the subject to get,

$x+4=2y^2$

$\Rightarrow \frac{x+4}{2}=y^2$

$\Rightarrow \pm \sqrt{\frac{x+4}{2}}=y$

But the given interval is $x\geq 0$ , This implies that, $y\geq 0$ .

$y=\sqrt{\frac{x+4}{2}}$

4 0

2 years ago

Read 2 more answers