(-1,2) rotated 180 degrees about the origin

there are a total of 122 countries in Africa, Europe, and North America. Europe has twice as many countries as North America, an

lana66690 [7]

E = 2N

A = E + 7 = 2n + 7

n + 2n + 2n +7 = 122

8 0

2 years ago

1. Which describes the intersection of plane A and line m?

NeTakaya

1. The intersection between plane A and line n is the point x
2. Since the right angle is bisected, the two smaller angles produced have measures of 45 degrees.
<span>c. m∠CEB = 45°
3. There is only 1 line that can be drawn between J and K</span><span />

4 0

3 years ago

Read 2 more answers

0.0508 written in 2 significant<br>figures is?

mojhsa [17]

0.05

0.0008

i think this is what u are talking about right

if not im srry i don't now

5 0

3 years ago

In quadrilateral WXYZ, WC = 2x + 5 and CY = 3x + 2. What must x equal for quadrilateral WXYZ to be a parallelogram?

Drupady [299]

The diagonals of a parallelogram bisect each other.
Therefore WC = CY.
That is,
2x + 5 = 3x + 2
Subtract 2x from each side.
5 = 3x - 2x + 2
5 = x + 2
Subtract from each side.
5 - 2 = x + 2 - 2
3 = x

Answer: x = 3

4 0

3 years ago

Read 2 more answers

Refrigerators in a random sample of 60 refrigerators, the mean repair cost was $150.00 and the standard deviation was $15.50. Co

worty [1.4K]

Answer:

The 99% confidence interval is given by ($144.677;$155.323)

We are confidenct at 99% that the true mean for the reapir cost of refrigerators is between 144.677 and 155.323.

Step-by-step explanation:

1) Notation and definitions

n=60 represent the sample size

$\bar X= 150$ represent the sample mean

$s=15.5$ represent the sample standard deviation

m represent the margin of error

Confidence =99% or 0.99

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".

2) 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 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . The degrees of freedom are given by: