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valentinak56 [21]

3 years ago

5

in a store parking lot, the ratio of blue cars to silver cars is 2 : 3. there are 24 blue cars how many silver cars are in the l

ot ?

1 answer:

wolverine [178]3 years ago

8 0

Answer: 36

Step-by-step explanation:

There is 50% more silver cars then blue cars

Take 24 x 1.5 (50% more) and you get 36

-Gage Millar, Algebra 2 tutoe

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Write the set of points from −8 to −2 but excluding −3 and −2 as a union of intervals

Sauron [17]

If you're only dealing with integers, then the answer is:

[-8 , -3)

If you're dealing with real numbers, then the answer is:

[-8, -3)∪(-3, -2)

3 0

3 years ago

A population has a mean of 200 and a standard deviation of 50. Suppose a sample of size 100 is selected and x is used to estimat

zmey [24]

Answer:

a) 0.6426 = 64.26% probability that the sample mean will be within +/- 5 of the population mean.

b) 0.9544 = 95.44% probability that the sample mean will be within +/- 10 of the population mean.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal probability distribution

When the distribution is normal, we use 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.

Central Limit Theorem

The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

In this question, we have that:

$\mu = 200, \sigma = 50, n = 100, s = \frac{50}{\sqrt{100}} = 5$

a. What is the probability that the sample mean will be within +/- 5 of the population mean (to 4 decimals)?

This is the pvalue of Z when X = 200 + 5 = 205 subtracted by the pvalue of Z when X = 200 - 5 = 195.

Due to the Central Limit Theorem, Z is:

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

X = 205

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

$Z = \frac{205 - 200}{5}$

$Z = 1$

$Z = 1$ has a pvalue of 0.8413.

X = 195

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

$Z = \frac{195 - 200}{5}$

$Z = -1$

$Z = -1$ has a pvalue of 0.1587.

0.8413 - 0.1587 = 0.6426

0.6426 = 64.26% probability that the sample mean will be within +/- 5 of the population mean.

b. What is the probability that the sample mean will be within +/- 10 of the population mean (to 4 decimals)?

This is the pvalue of Z when X = 210 subtracted by the pvalue of Z when X = 190.

X = 210

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

$Z = \frac{210 - 200}{5}$

$Z = 2$

$Z = 2$ has a pvalue of 0.9772.

X = 195

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

$Z = \frac{190 - 200}{5}$

$Z = -2$

$Z = -2$ has a pvalue of 0.0228.

0.9772 - 0.0228 = 0.9544

0.9544 = 95.44% probability that the sample mean will be within +/- 10 of the population mean.

7 0

3 years ago

Can u explain how u got the answer

Tems11 [23]

Answer:

10 degrees Celsius

Step-by-step explanation:

So, the question is asking for the difference between -8 and 2.

-----------------------------------------------------------------------------------------------------------------

Explanation 1:

2 - (-8) = ?

2 + 8 = ?

10 = ?

-----------------------------------------------------------------------------------------------------------------

Explanation 2:

|2| - 0 = 2

|-8| - 0 = 8

2 + 8 = 10

6 0

3 years ago

Segment AB has point A located at (4, 2). If the distance from A to B is 3 units, which of the following is the coordinate for p

olganol [36]

The distance between two points is given by:
d² = (x₂-x₁)² + (y₂ - y₁)²
9 = (x₂ - 4)² + (y₂ - 2)²
Now, we can check different ordered pairs in this equation to see which satisfies it:
The one that satisfies this equation is (4 , -1).

3 0

3 years ago

Read 2 more answers

James is 105 pounds. His coach

qaws [65]

You have to do 12 times 4, which equals 48. So 48 pounds in a year. 105 plus 48 would be 153 so that would be his weight by next year

8 0

3 years ago