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3 years ago

How to simplify the expression (6+2)2 to the second power-4x3 using order of operations

1 answer:

4 0

The answer would be 28.
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Here's my work:

Remember PEMDAS:
- Parentheses
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Also, remember to always go left to right.

(6+2)^2-4*3
Square everything in the parenthesis.

36+4-4*3
Multiply where you see a multiplication symbol from left to right.

36+4-12
Add.

40-12
Subtract.

28
Done!
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I hope I was able to guide and help you on this.

You might be interested in

Why does the multiplicative inverse of a number have the same sign as the number?

denis23 [38]

<span>Look at the definition of multiplicative inverse. If two numbers are multiplicative inverses of each other, then by definition, their product will be equal to 1. And 1 is a positive number. If both numbers being multiplied are positive, then the result is positive. And of both numbers being multiplied are negative, then the result is still positive. But if one number is positive and the other is negative, then the result is negative. So if you want a positive result, then both numbers you're multiplying have to have the same sign. And since we want a result of 1 for multiplicative inverses and since 1 is positive, then the numbers being multiplied have to have the same sign.</span>

7 0

3 years ago

An SRS of 350 high school seniors gained an average of x¯=21 points in their second attempt at the SAT Mathematics exam. Assume

Lynna [10]

Answer:

a) $21-2.58\frac{52}{\sqrt{350}}=13.83$

$21+2.58\frac{52}{\sqrt{350}}=28.17$

So on this case the 99% confidence interval would be given by (13.83;28.17)

b) $ME=2.58\frac{52}{\sqrt{350}}=7.17$

c) $ME=2.58\frac{52}{\sqrt{100}}=13.42$

d) D. Decreasing the sample size increases the margin of error, provided the confidence level and population standard deviation remain the same.

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".

Part a

$\bar X=21$ represent the sample mean

$\mu$ population mean (variable of interest)

$\sigma=52$ represent the population standard deviation

n=350 represent the sample size

99% confidence interval

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 $z_{\alpha/2}=2.58$

Now we have everything in order to replace into formula (1):

$21-2.58\frac{52}{\sqrt{350}}=13.83$

$21+2.58\frac{52}{\sqrt{350}}=28.17$

So on this case the 99% confidence interval would be given by (13.83;28.17)

Part b

The margin of error is given by:

$ME=2.58\frac{52}{\sqrt{350}}=7.17$

Part c

The margin of error is given by:

$ME=2.58\frac{52}{\sqrt{100}}=13.42$

Part d

As we can see when we reduce the sample size we increase the margin of error so the best option for this case is:

D. Decreasing the sample size increases the margin of error, provided the confidence level and population standard deviation remain the same.

6 0

3 years ago

P(x)=(x-2)(x-3)(x+7) find the constant term

hram777 [196]

Short method: multiply constants
$= ( - 2) \times ( - 3) \times (7) \\ = 6 \times 7 \\ = 42$

Long mothod: expand it
$= ( {x}^{2} - 5x + 6)(x + 7) \\ = ... \\ = ... + 42$

Answer: 42

5 0

3 years ago

1/3 + a = 5/4<br> A=? ..........................................................

NARA [144]

11/12 I’m pretty sure

3 0

2 years ago

Is my answer correct? If not what’s the right answer

pochemuha

Answer:

Yup, 27 is correct!

Step-by-step explanation:

5(7)-8

= 35 - 8

= 27

8 0

3 years ago

Read 2 more answers