Determine if the expression -a^3b^5 is a polynomial or not. If it is a polynomial, state

The librarian noticed that 60% of seventh graders checked out fantacy books. About how many of 240 seventh graders would check o

ehidna [41]

Answer:

The correct answer is 144.

Step-by-step explanation:

The librarian noticed that 60% of total seventh graders checked out fantasy books from the library.

Total number of seventh graders is given to be 240.

Number of seventh grade students who checked out fantasy books = 60% of 240 = 0.6 × 240 = 144.

Thus out of 240 seventh graders 144 of them would check out a fantasy book from the library.

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3 years ago

In the university library elevator there is a sign indicating a 16-person limit as well as a weight limit of 2750 pounds. Suppos

Alona [7]

Answer:

0.039 = 3.9% probability that the random sample of 16 people in the elevator will exceed the weight limit

Step-by-step explanation:

To solve this question, we need 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 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 $s = \frac{\sigma}{\sqrt{n}}$ .