All categories

3 years ago

Please help me? Show your work please! I give brainiest! (Or whatever it’s called :) )

Mathematics

1 answer:

azamat3 years ago

8 0

You need to find the hypotenuse of the right triangle.

4² + 9² = c²
16 + 81 = c²
97 = c²
9.85 = c

There are 5,280 ft in a mile.
Multiply 9.85 by 5,280.

9.85 × 5,280 = 52,008
Multiply 52,008 by 110.

52,008 × 110 = <span>5,720,880

The estimated cost for constructing the street would be $</span>5,720,880.

You might be interested in

I need a answer soon please!

Evgesh-ka [11]

Answer:

Let there were total x people at the conference

so 32%of x is 216

32/100×x=216

x=216×100/32

x=675

So total people present at the conference were 675

8 0

2 years ago

Help with math equation <br> 15 Points!!

Yanka [14]

Step 2 because the answer is 1 is simplified

4 0

3 years ago

Dividir entre la raíz más cercana

inna [77]

Where is the question ?

7 0

1 year ago

Renee is sewing a quilt whose pattern contains right triangles.

Mashutka [201]

Answer:

8 inches

Step-by-step explanation:

The area of a triangle is ...

A = 1/2bh

Filling in the given values, we have ...

24 = 1/2b(6)

24/3 = b = 8 . . . . . divide by the coefficient of b

The base of each triangular quilt piece is 8 inches long.

7 0

3 years ago

SAT scores are normed so that, in any year, the mean of the verbal or math test should be 500 and the standard deviation 100. as

vovangra [49]

Answer:

a) $P(X>625)=P(\frac{X-\mu}{\sigma}>\frac{625-\mu}{\sigma})=P(Z>\frac{625-500}{100})=P(Z>1.25)$

$P(Z>1.25)=1-P(Z$

b) $P(400$

$P(-1$

c) $z=-0.842$

And if we solve for a we got

$a=500 -0.842*100=415.8$

So the value of height that separates the bottom 20% of data from the top 80% is 415.8.

Step-by-step explanation:

Previous concepts

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 Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".

Part a

Let X the random variable that represent the SAT scores of a population, and for this case we know the distribution for X is given by:

$X \sim N(500,100)$

Where $\mu=500$ and $\sigma=100$

We are interested on this probability

$P(X>625)$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(X>625)=P(\frac{X-\mu}{\sigma}>\frac{625-\mu}{\sigma})=P(Z>\frac{625-500}{100})=P(Z>1.25)$

And we can find this probability using the complement rule and with the normal standard table or excel:

$P(Z>1.25)=1-P(Z$

Part b

We are interested on this probability

$P(400$

And the best way to solve this problem is using the normal standard distribution and the z score given by:

$z=\frac{x-\mu}{\sigma}$

If we apply this formula to our probability we got this:

$P(400$

And we can find this probability with this difference:

$P(-1$

And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.

$P(-1$

Part c

For this part we want to find a value a, such that we satisfy this condition:

$P(X>a)=0.8$ (a)

$P(X$ (b)

Both conditions are equivalent on this case. We can use the z score again in order to find the value a.

As we can see on the figure attached the z value that satisfy the condition with 0.2 of the area on the left and 0.8 of the area on the right it's z=-0.842. On this case P(Z<-0.842)=0.2 and P(Z>-0.842)=0.8

If we use condition (b) from previous we have this:

$P(X$

$P(z$

But we know which value of z satisfy the previous equation so then we can do this:

$z=-0.842$

And if we solve for a we got

$a=500 -0.842*100=415.8$

So the value of height that separates the bottom 20% of data from the top 80% is 415.8.

8 0

3 years ago