All categories

3 years ago

Find the area of a semicircle

Mathematics

2 answers:

Furkat [3]3 years ago

6 0

Answer:

18pi, or 56.52

Step-by-step explanation:

To start off, if you were to find the area of any whole circle, you would use the formula: pi x radius^2 = area of circle

However, since this is a semi-circle (half of a whole circle) you would divide the whole expression by 2, and then solve:

(pi x radius^2)/2 = area of semi-circle

(pi x 6^2)/2 = area of semi-circle

(36 x pi)/2 = area of semi-circle

18 x pi = area of semi-circle

18 x 3.14 = area of semi-circle

56.52 = area of semi-circle

Inessa [10]3 years ago

6 0

The area of a circle is

$\pi \: {r}^{2}$

So the area of a semicircle would be half of that, or

$\frac{\pi}{2} {r}^{2}$

So just plug in the radius, six, to get this

$18\pi$

You might be interested in

Bad gums may mean a bad heart. Researchers discovered that 82% of people who have suffered a heart attack had periodontal diseas

saveliy_v [14]

Answer:

37.27% probability that he or she will have a heart attack.

Step-by-step explanation:

Bayes Theorem:

Two events, A and B.

$P(B|A) = \frac{P(B)*P(A|B)}{P(A)}$

In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.

In this question:

Event A: Periodontal disease

Event B: Heart attack

Researchers discovered that 82% of people who have suffered a heart attack had periodontal disease, an inflammation of the gums.

This means that $P(A|B) = 0.82$

Only 33% of healthy people have this disease.

This means that $P(A) = 0.33$

Suppose that in a certain community heart attacks are quite rare, occurring with only 15% probability.

This means that $P(B) = 0.15$

If someone has periodontal disease, what is the probability that he or she will have a heart attack

$P(B|A) = \frac{0.15*0.82}{0.33} = 0.3727$

37.27% probability that he or she will have a heart attack.

6 0

2 years ago

Behind my math class help pls

vladimir2022 [97]

Answer:

Please check the explanation.

Step-by-step explanation:

Part a)

Given that the two parallel lines are crossed by a transversal line.

Given that

m∠2 = 2x + 54 and m∠6 = 6x - 11

Angle ∠2 and ∠6 are corresponding angles.

Corresponding angles are congruent.

Thus,

m∠2 = m∠6

2x + 54 = 6x - 11

flipe the equation

6x - 11 = 2x + 54

subtract 2x from both sides

6x - 2x - 11 = 2x - 2x + 54

4x - 11 = 54

adding 11 to both sides

4x - 11 + 11 = 54 + 11

4x = 65

dvide both sides by 4

4x/4 = 65/4

x = 16.2500 (round to 4 decimal places)

Part b)

We have already determined

x = 16.2500

Given

m∠2 = 2x + 54

substitute x = 16.2500 in the euation

= 2(16.2500) + 54

= 86.5°

As angle ∠2 and angle ∠1 lie on a straight line. Hence, the sum of their angles must be 180°.

i.e.

m∠1 + m∠2 = 180°

substituting m∠2 = 86.5° in the equation

m∠1 + 86.5° = 180°

subtracting 86.5° from both sides

m∠1 + 86.5° - 86.5° = 180° - 86.5°

m∠1 = 93.5°

Therefore, the measure of angle m∠1 is:

m∠1 = 93.5°

4 0

2 years ago

A cylindrical cooler has a diameter of 30 inches and a height of 24 inches . If a cup has a diameter of 3 inches and a height of

Aleks04 [339]

Answer:

The answer to your question is 600 cups

Step-by-step explanation:

Data

Cylinder Cup

diameter = 30 in diameter = 3 in

height = 24 in height = 4 in

Process

1.- Calculate the volume of the cylinder

Volume = πr²h

-Substitution

Volume = (3.14)(30/2)²(24)

-Simplification

Volume = (3.14)(15)²(24)

Volume = (3.14)(225)(24)

-Result

Volume = 16959 in³

2.- Calculate the volume of the cup

Volume = (3.14)(3/2)²(4)

-Simplification

Volume = (3.14)(1.5)²(4)

Volume = (3.14)(2.25)(4)

-Result

Volume = 28.26 in³

3.- Divide the volume of the cylinder by the volume of the cup

Number of full cups = 16959 in³ / 28.26 in³

Number of full cups = 600

8 0

2 years ago

Read 2 more answers

a person invest in 9000 in a bank. the bank pays 5% interest compounded semi annually. to the nearest tenth of a year, how long

QveST [7]

Answer:

10.1 years.

Step-by-step explanation:

It is given that,

Principal = 9000

Rate of interest = 5%

No. of times interest compounded = 2 times in an year

Amount after certain time = 14800

The formula for amount:

$A=P(1+\frac{r}{n})^{nt}$

where, P is principal, r is rate of interest, n is no. of times interest compounded in an year and t is time in years.

Substitute the given values in the above formula.

$14800=9000(1+\frac{0.05}{2})^{2t}$

$\frac{14800}{9000}=(1+0.025)^{2t}$

$1.644=(1.025)^{2t}$

Taking log both sides.

$\log(1.644)=\log(1.025)^{2t}$

$\log(1.644)=2t\log(1.025)$ $[\because \log a^b=b\log a]$

$\frac{\log(1.644)}{2\log(1.025)}=t$

$t=10.066$

$t=10.1$

Therefore, the required time is 10.1 years.

3 0

2 years ago

Miguel's scooter can travel at a maximum speed of 45 miles per hour. Which inequality models all the speeds, at which Miguel's s

Iteru [2.4K]

Answer:

I can't put the symbol in but less then or equal to 45mph

Step-by-step explanation:

4 0

2 years ago