Find the area of a circle with a diameter of 4.

Mathematics

2 answers:

Oliga [24]3 years ago

6 0

area of circle =22/7×4=12.56

kirill [66]3 years ago

6 0

Answer: 12.56

Explanation:

Find area of a circle:

Form: A = pi x d^2/4
d = 4 (given)
Pi = 3.14

=> A =3.14 x 4^2/4
A = 3.14 x 4
A = 12.56

You might be interested in

Please help I'm stuck on this questions thanks

polet [3.4K]

So its asking for basically the percentage of the first number out of the second.

3. 25/50 = 50%
4. 125/75 = 167%
5. 32/28 = 114%
6. 7/10 = 70%

Hope this helped! :)

6 0

3 years ago

Please help me in the box below

Fynjy0 [20]

1.330
2.930
3.30
4.80
5.90
6.140
7.10
8.110

6 0

3 years ago

Read 2 more answers

Gabriela has dinner at a cafe and the cost of her meal is $45.00.Because of the service, she wants to leave 15% tip.

goblinko [34]

Answer: $51.75

Step-by-step explanation:

7 0

3 years ago

A ladder 16 feet long is leaning against the wall of a tall building. The base of the ladder is moving away from the wall at a r

svet-max [94.6K]

Answer:

a. 0.588

b. 0.0722

c. 4.576 sqft/sec

Step-by-step explanation:

Let b and h denote the base and height as indicated in the diagram. By pythagoras theorem, $h^2 + b^2 = 16^2 = 256 \dotsc\;(1)$ because it is a right angle triangle.

It is given that $\frac{db}{dt} = 1$

Now differentiate (1) with respect to t (time) :

$\displaystyle{2h\frac{dh}{dt} + 2b\frac{db}{dt} = 0 \implies \frac{dh}{dt} = -\frac{b}{h} \frac{db}{dt}}$

$\displaystyle{=-\frac{b}{\sqrt{256 - b^2}} \frac{db}{dt} = -\frac{8}{13.856} \times 1 = -0.588}$

The minus sign indicates that the value of h is actually decreasing. The required answer is 0.588.

b. From the diagram, infer that $16 \sin{\theta} = b$ . When b = 8, then $\theta = \arcsin{0.5} = \ang{30}$ .

Differentiate the above equation w.r.t t

$\displaystyle{16 \cos{\theta} \frac{d\theta}{dt} = \frac{db}{dt} \implies \frac{d\theta}{dt} = \frac{1}{16 \cos{\theta}} = \frac{1}{13.856} = \mathbf{0.0722}}$