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Vesna [10]
2 years ago
14

a circle has an area of 81 3.14 units . what is the diameter in terms of 3.14a circle has an area of 81 Pi square units what is

the diameter of the circle
Mathematics
2 answers:
poizon [28]2 years ago
8 0

Answer:

18 units

Step-by-step explanation:

\pi r^2=81\pi

Solve for r:

\pi r^2=81\pi \\r^2=81\\r=9

Knowing diameter is 2*r, we can apply the formula to find diameter

d=2*r\\d=2*9\\d=18

Sunny_sXe [5.5K]2 years ago
4 0
You have posted 2 separate questions here.  Please, next time, separate them with a blank line:

<span>A circle has an area of 81 3.14 units . what is the diameter in terms of 3.14?

I'd prefer you write this as 
"</span><span>A circle has an area of 81 pi units . what is the diameter in terms of pi?

Area of a circle = A = pi*r^2.  Note that r= diameter / 2.  Here, the area is 81 pi square units, or 9^2 * pi square units, which means that the radius is 9 units.  The diameter is then 2(9 units) = 18 units.


Your second question, separated from the first, is:

"</span><span>a circle has an area of 81 Pi square units what is the diameter of the circle?"
</span><span>
Use the following formula or formulas:  d = 2*r; A = pi*r^2; A = pi*(d/2)^2.  Find r first, and then find d.

</span>
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Aaron participates in a walkathon for charity. He has a sponsor who has pledged a base donation of $2 for the first mile he walk
tino4ka555 [31]

Answer:

total amount donated when aaron walks n miles = $2 + $3(n-1)

Step-by-step explanation:

Aaron participates in a walkathon for charity. He has a sponsor who has pledged a base donation of $2 for the first mile he walks and then a certain dollar amount for each additional mile he walks. Based on this pledge, if Aaron walks 8 miles, the sponsor will donate a total of $23 to the charity.

Write a formula that can be used to determine the amount of money this sponsor donates when Aaron walks n miles.

total amount sponsor pays = base donations + (additional miles walked after first mile x amount paid)

when Aaron walks 8 miles

additional miles = 8 - 1 = 7

23 = 2 + 7x

23 - 2 = 7x

x = 3

additional amount paid is $3

total amount donated when aaron walks n miles = $2 + $3(n-1)

5 0
3 years ago
A shipment to a warehouse consists of 2,750 MP3 players. The manager chooses a random sample of 50
Juli2301 [7.4K]

MP3 players in the shipment which are likely to be defective is 330.

Step-by-step explanation:

• Probability is event of an occurrence which is uncertain.

• Probability always lies between 0 to 1.

• The sample of 50 MP3 has 6 defective, to solve it has to be converted.

• Convert percentage in 100 multiply numerator and denominator by 2.

• Result is 6/50 converted to 12/100, bring it to 0.12%.

• 12% is defected in 100% of sample.

• It is found here that 2750 is the population and 12% of 2750.

• 2750 * 0.12 = 330, defective pieces in 2750.

• There are three types of Classical,Empirical or Experimental.

• Classical are ‘n’ number of events find the probability occurrence.  

• Empirical or experimental is purely based on events.

5 0
3 years ago
What is the surface area of a cylinder that has the following measurements? area of each base: 50.24 ft2 area of lateral surface
irinina [24]

Answer:

TSA = 175.84 ft²

Step-by-step explanation:

We are given;

Lateral surface area; A_L = 75.36 ft²

Area of base; A_b = 50.24 ft²

Height of cylinder; h = 3ft

Formula for total surface area of Cylinder is;

TSA = 2πr² + 2πrh

Now, lateral surface area is given by the formula; A_L = 2πrh

Area of base is given by the formula;

A_b = πr²

Thus, let's apply these 2 formulas to the formula for total surface area;

TSA = 2(Area of base) + Lateral surface area

TSA = (2 * 50.24) + 75.36

TSA = 175.84 ft²

3 0
3 years ago
A field test for a new exam was given to randomly selected seniors. The exams were graded, and the sample mean and sample standa
Naya [18.7K]
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4 0
3 years ago
2. C is at (-5.1) &amp; D is at (7.6). Where is the midpoint on segment CD?​
topjm [15]

Answer:

1.25

Step-by-step explanation:

Find the average.

-5.1+7.6=2.5

2.5/2

1.25

6 0
3 years ago
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