11 y + 4 one step equations

Two cars that are 150 miles apart start driving toward each other on parallel roads. The average speed of the first car is 60 mi

timama [110]

Answer:

60t + 55t = 150

Step-by-step explanation:

I took the test. I know it's correct!!!

9 0

3 years ago

What is the difference between a quart and a half a gallon

Citrus2011 [14]

A quart is one half of a quart and a half is half of a gallon. A gallon is four quarts.

6 0

3 years ago

Read 2 more answers

(1 point) Suppose we want a 95% confidence interval for the average amount spent on books by freshmen in their first year at col

Ne4ueva [31]

Answer:

a) $n=(\frac{1.960(16)}{5})^2 =39.33 \approx 40$

So the answer for this case would be n=40 rounded up to the nearest integer

b) For this case if we see the formula for the margin of error

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (a)

We can see that the margin of error is inversely proportional to the sample size so if we want a samller margin of error we need a LARGER sample

Answer: LARGER

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

$\sigma=16$ represent the population standard deviation

n represent the sample size

Solution to the problem

Part a

The margin of error is given by this formula:

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (a)

And on this case we have that ME =5 and we are interested in order to find the value of n, if we solve n from equation (a) we got:

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

The critical value for 95% of confidence interval now can be founded using the normal distribution. And in excel we can use this formla to find it:"=-NORM.INV(0.025;0;1)", and we got $z_{\alpha/2}=1.960$ , replacing into formula (b) we got:

$n=(\frac{1.960(16)}{5})^2 =39.33 \approx 40$

So the answer for this case would be n=40 rounded up to the nearest integer

Part b

For this case if we see the formula for the margin of error

$ME=z_{\alpha/2}\frac{s}{\sqrt{n}}$ (a)

We can see that the margin of error is inversely proportional to the sample size so if we want a samller margin of error we need a LARGER sample

Answer: LARGER

5 0

3 years ago

Irene's account has $75 less than it did before on Monday. This is reasonable because she wrote checks for $200 but only deposit

hammer [34]

Alright, lets get started.

Given information : Irene writes the check of 200 $ . It means the amount is deducted form here account.

Irene deposited 125 $ in her account. Means this amount is added in her account.

Suppose her initial amount in account was x $.

When she writes the check of 200 $, the amount is deducted so new balance is (x - 200) .

When she deposit amount 125 $, it means , the new balance of her account will be: $x - 200 + 125 = x - 75$

Which shows her account is 75 $ less than her previous balance.

Hope it will help :)

8 0

4 years ago

How do I find the measure of the angle

eimsori [14]

Answer:

30°

Step-by-step explanation:

we can use the trigonometric functions

$\sin \theta=\frac{Op}{Hyp}\\\\Opposite=4\\\\Hypotenuse=8\\\\\Rightarrow \sin \theta = \frac{4}{8}\\\\\sin \theta =\frac{1}{2}\\\\\theta=\sin ^{-1}(\frac{1}{2})\\\\\thetha= 30$

3 0

3 years ago