I don't remember how to find x please help

Which ordered pair is a solution to the equation y = 6x - 4?

Yuri [45]

Answer:

Here are 3 different pairs (0,4) , (1,2) , (2,8)

Step-by-step explanation:

Hope this helped

7 0

2 years ago

Help please I need it:

jonny [76]

Answer:

Step-by-step explanation:

The number of sandwiches sold: 73

The cost to make one sandwich: S

The profit the band earns from one sandwich: 0.2S

The amount of money that the band recieves for selling one sandwich:

S + 0.2S

6 0

2 years ago

Jeff as a collection of hockey cards. His brother Steve had 10 more cards than Jeff. Steve gave Jeff all of his cards. Jeff ende

lesya [120]

Answer: 491 cards

Step-by-step explanation:

Given

Steve had 10 more cards than Jeff

Suppose Jeff has x cards

So, steve has x+10 cards

Steve handover his cards to Jeff

Now, Jeff has x+x+10=2x+10 cards

It must be equal to 992

$\Rightarrow 2x+10=992\\\Rightarrow 2x=982\\\Rightarrow x=491\ \text{cards}$

Jeff started with 491 cards

6 0

2 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: