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Evaluate each expression. Show step by step<br> 5(4-1)

djverab [1.8K]

Answer:

15

Step-by-step explanation:

5x4=20

5x-1=-5

20-5=15

5 0

3 years ago

Read 2 more answers

The Fratellis will be arrested if and only if the police believe Chunk. Question 9 options: 1) p ↔ q 2) p ∨ q 3) p → q 4) ~p 5)

Amiraneli [1.4K]

Answer:

Option 1) p ←→ q

Step-by-step explanation:

The given statement is a combination of two phrases with a connective word.

Phrase 1 - The Fratellis will be arrested.

We consider this phrase as phrase p.

Phrase 2 - If the police believe chunk.

Phrase q.

Now these statements p and q are connected with a connecting word "If only and only".

When two phrases are connected by the connecting words "Only and only if", this connecting word is called as biconditional operator.

p (connecting word) q

p ( If and only if) q

p ←→ q

Therefore, Option 1) p ←→ q is the answer.

3 0

2 years ago

A box contains 6 red and 5 blue marbles. Another box contains 5 red and 8 blue marbles. One box is selected at

dlinn [17]

Answer:

153\286

Step-by-step explanation:

A -box 1

B -box 2

B)- blue ball drawn

6 0

2 years ago

You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard devia

Arturiano [62]

Answer:

$n=(\frac{z_{\alpha/2} \sigma}{ME})^2$ (3)

$n=(\frac{2.58(54.5)}{5})^2 =790.846 \approx 791$

So the answer for this case would be n=791 rounded up to the nearest integer

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

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".

$\bar X$ represent the sample mean for the sample

$\mu$ population mean (variable of interest)

s represent the sample standard deviation

n represent the sample size

Solution to the problem

The confidence interval for the mean is given by the following formula:

$\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

Since the Confidence is 0.99 or 99%, the value of $\alpha=0.01$ and $\alpha/2 =0.005$ , and we can use excel, a calculator or a table to find the critical value. The excel command would be: "=-NORM.INV(0.005,0,1)".And we see that $z_{\alpha/2}=2.58$