8 times a certain number is added to 5 times a second number to give 184.

Is 16.5 a rational or irrational number

Mademuasel [1]

Answer:

It is rational

I'm sorry if it's wrong

Step-by-step explanation:

Rational: Stops

Irrational: Keeps going on

7 0

3 years ago

A company with a large fleet of cars wants to study the gasoline usage. They check the gasoline usage for 50 company trips chose

Nookie1986 [14]

Answer:

The 95% confidence interval is given by (25.71536 ;28.32464)

And if we need to round we can use the following excel code:

round(lower,2)

[1] 25.72

round(upper,2)

[1] 28.32

And the interval would be (25.72; 28.32)

Step-by-step explanation:

Notation and definitions

n=50 represent the sample size

$\bar X= 27.2$ represent the sample mean

$s=5.83$ represent the sample standard deviation

m represent the margin of error

Confidence =88% or 0.88

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".

Calculate the critical value tc

In order to find the critical value is important to mention that we don't know about the population standard deviation, so on this case we need to use the t distribution. Since our interval is at 88% of confidence, our significance level would be given by $\alpha=1-0.88=0.12$ and $\alpha/2 =0.06$ . The degrees of freedom are given by:

$df=n-1=50-1=49$

We can find the critical values in R using the following formulas:

qt(0.06,49)

[1] -1.582366

qt(1-0.06,49)

[1] 1.582366

The critical value $tc=\pm 1.582366$

Calculate the margin of error (m)

The margin of error for the sample mean is given by this formula:

$m=t_c \frac{s}{\sqrt{n}}$

$m=1.582366 \frac{5.83}{\sqrt{50}}=14.613$

With R we can do this:

m=1.582366*(5.83/sqrt(50))

m

[1] 1.304639

Calculate the confidence interval

The interval for the mean is given by this formula:

$\bar X \pm t_{c} \frac{s}{\sqrt{n}}$

And calculating the limits we got:

$27.02 - 1.582366 \frac{5.83}{\sqrt{50}}=25.715$

$27.02 + 1.582366 \frac{5.83}{\sqrt{50}}=28.325$

Using R the code is:

lower=27.02-m;lower

[1] 25.71536

upper=27.02+m;upper

[1] 28.32464

The 95% confidence interval is given by (25.71536 ;28.32464)

And if we need to round we can use the following excel code:

round(lower,2)

[1] 25.72

round(upper,2)

[1] 28.32

And the interval would be (25.72; 28.32)

6 0

3 years ago

Evaluate - 2/5- x + (-9/10) where x = 4/5.

zalisa [80]

Answer:

- 2 1/10

Step-by-step explanation:

-2/5 -x -9/10

Let x = 4/5

-2/5 - 4/5 - 9/10

Combine like terms

-6/5 - 9/10

Get a common denominator of 10

-6/5 * 2/2 - 9/10

-12/10 - 9/10

-21/ 10

Change this to a mixed number

10 goes into 21 2 times with 1 left over

-2 1/10

6 0

3 years ago

Read 2 more answers

Plzzz help!!!!!!!!!!!!!!!!

REY [17]

Answer:

B) The function has a maximum value of (1)

Step-by-step explanation:

The given function has a maximum value, as its curve is inverted. The maximum value is the largest (y) value that a function can attain. As one can see, this value is (1), because the (y-coordinate) of the highest point on its curve is (1). This function has no minimum value, its endpoints go on infinitely in a negative direction.

3 0

3 years ago

A city pool has 3 wading pools. Each pool is in the shape of a parallelogram with a

Vikki [24]

Answer:

i think it's 13.44

Step-by-step explanation:

im not really sure, but let me know if im wright pls!!

hope this helped!!

6 0

3 years ago