13.) –3(y+3)=2y+3<br> What is the answer to this

Suppose 40% of the population of pre-teens have a TV in their bedroom. If a random sample of 500 pre-teens is drawn from the pop

natita [175]

Answer:

The probability that 44% or fewer of the pre-teens have a TV in their bedroom is 96.64%.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

For a proportion p in a sample of size n, we have that $\mu = p, \sigma = \sqrt{\frac{p(1-p)}{n}}$

In this problem:

$\mu = 0.4, \sigma = \sqrt{\frac{0.4*0.6}{500}} = 0.0219$

The probability that 44% or fewer of the pre-teens have a TV in their bedroom is

This is the pvalue of Z when X = 0.44. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{0.44 - 0.4}{0.0219}$

$Z = 1.83$

$Z = 1.83$ has a pvalue of 0.9664

The probability that 44% or fewer of the pre-teens have a TV in their bedroom is 96.64%.

7 0

4 years ago

A word game has 100 tiles with different letters , if letters are drawn 7 at a time, approximately how many possible letter comb

Talja [164]

Answer: 16 007 560 800 possible letter combinations.
Explanation: Now, we don't care about the order in which they are picked, so it's a little bit different to how permutation probability and combinations work.
Since we don't care about order, these two are identical:

123a
12a3

They have the same letters in their sequence, so they won't form a new word.
Now, let's understand how combinatorics work compared to permutations.

Combinatorics work out a list of combinations that you can have, provided that they all have different values (123 is not the same as 234, they are different combinations), however permutations focus solely on ordered figures (123 may be the same as 321 in combinatorics, but they yield a new set in permutations).

Thus, if we don't care about order, let's write up a formula:
If we have 100 tiles to fill 100 places, we have 100! combinations, provided that they are all different letters.
But we only want to pick 7 and sort them out.

Thus, our equation is $\frac{100!}{7!(100 - 7)!} = 16 007 560 800$
This is our $^{n}C_r$ formula, and it's important to remember this formula.

8 0

3 years ago

Which polynomial correctly combines the like terms and expresses the given polynomial in standard form? 8mn5 – 2m6 + 5m2n4 – m3n

MaRussiya [10]

Answer:

$-6m^{6}+n^{6}+7mn^{5}+14m^{2}n^{4}-5m^{3}n^{3}$

Step-by-step explanation:

given polynomial is:

$8mn^{5}-2m^{6}+5m^{2}n^{4}-m^{3}n^{3}+n^{6}-4m^{6}+9m^{2}n^{4}- mn^{5}-4m^{3}n^{3}$

write similar terms together,

$-2m^{6}-4m^{6}+n^{6}+8mn^{5}-mn^{5}+5m^{2}n^{4}+9m^{2}n^{4}-m^{3}n^{3}-4m^{3}n^{3}$

$-6m^{6}+n^{6}+7mn^{5}+14m^{2}n^{4}-5m^{3}n^{3}$

Hence, polynomial in standard form $-6m^{6}+n^{6}+7mn^{5}+14m^{2}n^{4}-5m^{3}n^{3}$

8 0

3 years ago

A cereal box is labeled as containing 16 ounces. Suppose the production line manager tests to determine whether the average weig

meriva

Answer:

Lyrics A

Step-by-step explanation:

Problem statement does not mention anything about conditions of the test, so we dont know if the experiment was correctly done, but we know the kind of problem we are facing here is concerning a normal distribution

Then assuming the test was done by knowledgeable people, which means:

- they got correct information from the population

-sample was big enough

- level of confidence was acceptable for the test ( approximately 95 %) - Alternative hypothesis took into account two tails test

-Test was evaluated according to sample size

-And finally calculations were right

Under the above mentioned conditions, they tested the hypotesis H₀ = μ₀ = 16 ounces and they got results that implies the acceptance of such hypothesis (that means the null hypothesis should not be rejected), and the answer is lyrics A

7 0

3 years ago

What is 5 3/4 subtracted by 5/8

svet-max [94.6K]

Answer:

$5\frac{1}{8}$

Step-by-step explanation:

5 3/4 = 23/4

(23/4)2 = 46/8

46/8 - 5/8 = 41/8 = 5 1/8

7 0

3 years ago

13.) –3(y+3)=2y+3 What is the answer to this