What is the value of this expression when a= 3 and b- -2? (3a^-2 b^6)/(2a^-1 b^5)^2

A test is used to assess readiness for college. In a recent year, the mean test score was 20.3 and the standard deviation was 4

Vlada [557]

Answer:

$\mu = 20.3$

$\sigma = 4.9$

And we can find the limits in order to consider values as significantly low and high like this:

$Low\leq \mu -2 \sigma= 20.3- 2*4.9 = 10.5$

$High\geq \mu +2 \sigma= 20.3+ 2*4.9 = 30.1$

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".

Solution to the problem

For this case we can consider a value to be significantly low if we have that the z score is lower or equal to - 2 and we can consider a value to be significantly high if its z score is higher tor equal to 2.

For this case we have the mean and the deviation given:

$\mu = 20.3$

$\sigma = 4.9$

And we can find the limits in order to consider values as significantly low and high like this:

$Low \leq \mu -2 \sigma= 20.3- 2*4.9 = 10.5$

$High\geq \mu +2 \sigma= 20.3+ 2*4.9 = 30.1$

6 0

3 years ago

The sum of four and the product of three and a number x.

KIM [24]

Answer:

Step-by-step explanation:

The product of three and a number x: 3 · x = 3x

The sum of four and the product of three and a number x:

4 + 3x

8 0

3 years ago

Subduction zones occur at the boundaries between

ycow [4]

D - tectonic plates
Subduction is a geological process that takes place at convergent boundaries of tectonic plates where one plate moves under another and is forced to sink due to high gravitational potential energy into the mantle. Regions where this process occurs are known as subduction zones

7 0

3 years ago

Read 2 more answers

Someone please help or i’ll be failing geometry this year

Vlad [161]

Step-by-step explanation:

I don't know what constructions you were taught.

a "similar" triangle is a triangle with exactly the same angles as the other triangle, but the lengths of all sides are stretched or shortened by the same scaling factor f.

by saying 1:2 she means the second triangle should have sides with twice the lengths of the first triangle (f=2).

and the extra challenge - same basic thing. she allows you to pick one of the two triangles as reference. and then you need to draw a third triangle (again with the same angles) with the side lengths extended by the scaling factor f of 4/3.

I would draw the triangles right on top of each other with the same starting corner (let's call it A) for all 3.

we would get the triangles ABC, AMN and AXY.

the points B and C would be then halfway on AM and AN.

and M and N would then a bit before X and Y on AX and AY.

the beauty is, you only need to construct 2 sides of every new triangle down to the new endpoints. the third side is automatically scaled correctly, and you only need to connect these new endpoints.

let's assume you draw a triangle (just very simple) ABC with all side lengths being 3. so, AB=3, AC=3, BC=3.

now you draw AMN by extending AB and AC to a side length of 6 (f=2) creating M and N, and you connect M and N.

and then you can create the third triangle AXY by extending AM and AN by a factor of 4/3 to side lengths of 8 (4/3 × 6 = 8) creating new end points X and Y. and you connect X and Y.

and that is it. all 3 triangles are similar (the same angles), and all sides of a triangle have the same length ratio to the sides of the other triangle(s).

4 0

2 years ago

LaVelle is making a pitcher of caffe mocha. For each ounce of chocolate syrup, she uses five ounces of coffee. How many ounces o

ipn [44]

Answer:

40 ounces of coffee

Step-by-step explanation:

we know that

To make caffe mocha, LaVelle uses one ounce of chocolate syrup,and five ounces of coffee

so

To make 6 ounces of caffe mocha (one ounce of chocolate syrup plus 5 ounces of coffe), LaVelle uses one ounce of chocolate syrup,and five ounces of coffee

using proportion

Find out how many ounces of coffee does she need to make 48 ounces of caffe mocha

Let

x ---> ounces of coffee needed to make 48 ounces of caffe mocha

$\frac{6}{5}\ \frac{oz\ caffe\ mocha}{oz\ coffee} =\frac{48}{x}\ \frac{oz\ caffe\ mocha}{oz\ coffee}\\\\x=48(5)/6\\\\x=40\ oz\ coffee$

3 0

3 years ago