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3 years ago

Can someone help me with the first 3 as it is my first time doing it ? I need help

Mathematics

1 answer:

Fed [463]3 years ago

7 0

You problem is you don't have any problem. You have a bunch of formulas for the perimeter and area of some shapes.

As for using the formulas, usually you're given all but one of the variables and you can solve for the remaining one.

Notice how the triangle result doesn't have area as a function of a, b and c. That's called Heron's formula and is usually not taught to secondary school students. I don't like to teach it either because Archimedes' Theorem is so much better:

The sides a,b,c and area S of a triangle satisfy

$16S^2 = (a+b+c)(-a+b+c)(a-b+c)(a+b-c) = 4a^2b^2-(c^2-a^2-b^2)^2 = (a^2+b^2+c^2)^2 - 2(a^4+b^4+c^4)$

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Which is a question you probably would ask when comparison shopping? A. What is the warranty on this product versus another prod

densk [106]

Answer:

The answer is B.

Step-by-step explanation:

4 0

3 years ago

According to a study conducted by the Gallup Organization, the the proportion of Americans who are afraid to fly is 0.10. A rand

notsponge [240]

Answer: 0.1457

Step-by-step explanation:

Let p be the population proportion.

Given: The proportion of Americans who are afraid to fly is 0.10.

i.e. p= 0.10

Sample size : n= 1100

Sample proportion of Americans who are afraid to fly = $\hat{p}=\dfrac{121}{1100}=0.11$

We assume that the population is normally distributed

Now, the probability that the sample proportion is more than 0.11:

$P(\hat{p}>0.11)=P(\dfrac{\hat{p}-p}{\sqrt{\dfrac{p(1-p)}{n}}}>\dfrac{0.11-0.10}{\sqrt{\dfrac{0.10(0.90)}{1100}}})\\\\=P(z>\dfrac{0.01}{0.0090453})\ \ \ [\because z=\dfrac{\hat{p}-p}{\sqrt{\dfrac{p(1-p)}{n}}} ]\\\\=P(z>1.1055)\\\\=1-P(z\leq1.055)\\\\=1-0.8543=0.1457\ \ \ [\text{using z-table}]$

Hence, the probability that the sample proportion is more than 0.11 = 0.1457

3 0

3 years ago

a gift shop sells 160 wind chimes per month at $150 each. the owners estimate that for each $15 increase in price, they will sel

adell [148]

Answer:

The price per wind chime that will maximize revenue = $ 315

Step-by-step explanation:

Given - A gift shop sells 160 wind chimes per month at $150 each. the owners estimate that for each $15 increase in price, they will sell 5 fewer wind chimes per month.

To find - Find the price per wind chime that will maximize revenue.

Proof -

Given that,

Total Wind chimes selling = 160

Price of each Wind chime = $150

Now,

Given that, for each $15 increase in price, they will sell 5 fewer wind chimes per month.

So,

Let the price = 150 + 15x

So,

Number of wind Chimes sold per month = 160 - 5x

So,

Total Revenue, R = (150 + 15x)(160 - 5x)

= 24000 - 750x + 2400x - 75x²

= 24000 + 1650x - 75x²

⇒R(x) = 24000 + 1650x - 75x²

Differentiate R with respect to x , we get

R'(x) = 1650 - 150x

Now,

For Maximize Revenue, Put R'(x) = 0

⇒1650 - 150x = 0

⇒150x = 1650

⇒x = 1650/150

⇒x = 11

∴ we get

Price per Wind chime = $ 150 + 15(11)

= $ 150 + 165

= $ 315

So,

The price per wind chime that will maximize revenue = $ 315

3 0

3 years ago

Answer this world problem for me

inn [45]

Let's solve this problem step-by-step.

STEP-BY-STEP SOLUTION:

In order to find the answer, we need to do as follows:

Average no. of people per km^2 = total no. of people ÷ total no. of people

Average no. of people per km^2 = 1, 080, 264, 388 ÷ 2, 973, 190

Average no. of people per km^2 = 363.335134317

Now we need to round the answer to the nearest whole number. In this case, we will be rounding down as displayed below:

Average no. of people per km^2 = 363 people

ANSWER:

Therefore, the answer is:

There are an average of 363 people per km^2 of land in India.

Please mark as brainliest if you found this helpful! :)
Thank you <3

7 0

3 years ago

A square has a side that is (x-3) units long. If the area of the square is 126.5625 sq units, what is the value of x?

Kitty [74]

Answer:

14.25 units

Step-by-step explanation:

Area of a square= $l*b= (x-3)(x-3)=x^{2}-3x-3x+9=x^{2}-6x+9$