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3 years ago

What if equation does not have parethises

Mathematics

1 answer:

Luda [366]3 years ago

6 0

Do multiplication first than divide

first add an than subtract

You might be interested in

Which list shows the absolute values in order from least to greatest?

RoseWind [281]

To determine which list of absolute values is in order from least to greatest, you should Think of all of these fractions as positive values.

The reason is that the absolute value means the distance from zero. The lists that shows the distances from zero from least to greatest are:

1st: |-5/14|, |-4/7|, |6/7| AND
2nd: |-3/8|, |3/4|, |-7/8|

8 0

3 years ago

Estimate the minimum and maximum ages for typical textbooks currently used in college courses, then use the range rule of thumb

Maksim231197 [3]

Answer:

$n=(\frac{1.64(4)}{0.25})^2 =688.537 \approx 689$

So the answer for this case would be n=689 rounded up to the nearest integer

Step-by-step explanation:

Assuming this complete question: "Suppose that the minimum and maximum ages for typical textbooks currently used in college courses are 0 and 8 years. Use the range rule of thumb to estimate the standard deviation.

Estimate the minimum and maximum ages for typical textbooks currently used in college courses, then use the range rule of thumb to estimate the standard deviation. Next, find the size of the sample required to estimate the mean age (in years) of textbooks currently used in college courses. Use a 90% confidence level and assume that the sample mean will be in error by no more than 0.25 year."

Solution for the problem

First we need ti find the estimation for the standard deviation using the Rule of thumb, with the following formula:

$s \approx \frac{R}{4}$

Where R is the range defined as :

$R = Max - Min = 8-0 = 8$

So then the deviation would be approximately:

$s \approx 4$

Important 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 (ME) 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".

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{\sigma}{\sqrt{n}}$ (1)

And on this case we have that $ME =\pm 0.25$ and we are interested in order to find the value of n, if we solve n from equation (1) we got:

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

We can assume that the estimator for the population deviation from the rule of thumb is $\hat \sigma = s= 4$

The critical value for 90% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.05;0;1)", and we got $z_{\alpha/2}=1.64$ , replacing into formula (2) we got:

$n=(\frac{1.64(4)}{0.25})^2 =688.537 \approx 689$

So the answer for this case would be n=689 rounded up to the nearest integer

6 0

3 years ago

Please help, ik it looks easy but i cant do it, ill give brainliest

rjkz [21]

Answer:

Step-by-step explanation:

$(m+\frac{1}{m})=3\\cubing both sides\\(m+\frac{1}[m})^{3} =3^{3} \\m^3+\frac{1}{m^3}+3 m*\frac{1}{m}(m+\frac{1}{m})=27\\m^3+\frac{1}{m^3}+3*3=27\\m^3+\frac{1}{m^3}=27-9=18$

8 0

3 years ago

Can you guys help me with this math questions

dimulka [17.4K]

Answer:

2) $40 per shirt

3) 80/9 m = 8.9 m (nearest tenth)

Step-by-step explanation:

The first question has been answered here: brainly.com/question/27846862

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Question 2

Given information:

Previous sales = 300 shirts at $20 each
For every $1 increase in price, the number of sales diminishes by 5

Let $x$ = number of $1 increases

Let $y$ = total revenue (in dollars)

From the given information:

Price change of shirt: $(20 + x)$

Number of sales change: $(300 - 5x)$

Therefore, we can create a quadratic equation with the given information:

$\implies y = (20+x)(300-5x)$

As we need to find the maximum amount of revenue, we need to find the vertex of $y$ . As the equation is already factored, the quickest way to do this is to the find the mid-point of the zeros (since a quadratic curve is symmetrical).

$\begin{aligned}y & =0\\\implies (20+x)(300-5x) & =0\\\implies (20+x) & =0 \implies x=-20\\\implies (300-5x) & = 0 \implies x=60\end{aligned}$