Please help me ill give brainliest to correct answer when i can :)

MaRussiya [10]

I might be wrong but 9

9*2=18
18+7= 25
25 square root = 5

Answer is 9

7 0

2 years ago

The mean points obtained in an aptitude examination is 159 points with a standard deviation of 13 points. What is the probabilit

Korolek [52]

Answer:

0.4514 = 45.14% probability that the mean of the sample would differ from the population mean by less than 1 point if 60 exams are sampled

Step-by-step explanation:

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

Normal probability distribution:

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.

Central limit theorem:

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

In this problem, we have that:

$\mu = 159, \sigma = 13, n = 60, s = \frac{13}{\sqrt{60}} = 1.68$

What is the probability that the mean of the sample would differ from the population mean by less than 1 point if 60 exams are sampled?

This is the pvalue of Z when X = 159+1 = 160 subtracted by the pvalue of Z when X = 159-1 = 158. So

X = 160

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

By the Central Limit Theorem

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

$Z = \frac{160 - 159}{1.68}$

$Z = 0.6$

$Z = 0.6$ has a pvalue of 0.7257

X = 150

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

$Z = \frac{158 - 159}{1.68}$

$Z = -0.6$

$Z = -0.6$ has a pvalue of 0.2743

0.7257 - 0.2743 = 0.4514

0.4514 = 45.14% probability that the mean of the sample would differ from the population mean by less than 1 point if 60 exams are sampled

7 0

3 years ago

Answer this question Angie and her friends are 3/4 of a pizza.Her brother joe ate 2/3 of what was left.How much did joe eat?

Alja [10]

If Angie and her friends ate 3/4 of a pizza, that means that 1/4 is left.
Joe ate 2/3 of 1/4 of a pizza. To find out how much he ate, multiply 1/4 by 2/3.

$\frac{1}{4}* \frac{2}{3}= \frac{2}{12}$ because you multiply fractions straight across.

Your answer is 2/12 or 1/6 of the pizza

4 0

2 years ago

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Which digit is in the hundredths place? 18.36 8 3 1 6

Karolina [17]

Answer:

6.becuase after the decimal or "." it goes 00.tenth, hundredth, thousandth, and so on

Step-by-step explanation:

PLEASE GIVE BRAINLIEST OR 5 ⭐

4 0

1 year ago

Read 2 more answers