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3 years ago

Help me with this pls??

Mathematics

1 answer:

Vesnalui [34]3 years ago

7 0

Answer:

36.7

Step-by-step explanation:

Divide it into 2 shapes: the cylinder and the cone

The volume of the cylinder is 1^2 * (13-2) * pi = 11pi

The volume of the cone is 1^2 * 2 * 1/3 * pi = 2/3 pi

11pi + 2/3pi = 11 2/3 pi

11 2/3 pi is approx. 36.7

You might be interested in

If 40% of a number is 56 what was the original number

svp [43]

Percent is pars out of 100
40%=40/100=4/10=0.4
'of' means multiply
0.4 times something=56
divide both sides by 0.4
something=140

th enumber is 140

5 0

3 years ago

David is buying fish for his aquarium. Clown fish cost $12 each and angel fish cost $7 each. If he has $100 to spend, and he wan

Anni [7]

Answer:

6 clown fish and 4 angel fish

Step-by-step explanation:

lets say he bought 8 clown fish.

12*8 = 96

the last 4 dollars wont be used.

lets say he bought 7 clown fish-

12*7 = 84

100 - 84 = 16. 16 is not a multiple of 7.

lets say he bought 6 clown fish,

12*6 = 72

100 - 72 = 28

28/7 = 4

If David has $100 dollars to spend and wants to spend every dollar, he can buy 6 clown fish and 4 angel fish.

3 0

2 years ago

How to find the area of irregular figures

Cloud [144]

Instead, break down the shape into rectangles. Next, calculate the area of both rectangles and add them together. The area of the first rectangle is 72 square centimeters and the area of the second rectangle is 50 square centimeters. Together there are 72 + 50 = 122 square centimeters.

That is how u find a irregular figure..hope this help u

3 0

3 years ago

The area of a circular oil slick on the surface of the sea is increasing at a rate of [150m^2/s] how fast is the radius changing

Akimi4 [234]

Answer with Step-by-step explanation:

We are given that

$\frac{dA}{dt}=150m^2/s$

a.Radius =25 m

We have to find rate of change of radius.

We know that

Area of circle, $A=\pi r^2$

Differentiate w.r.t time

$\frac{dA}{dt}=2\pi r\frac{dr}{dt}$

Substitute the values then we get

$150=2\pi (25)\frac{dr}{dt}$

$\frac{dr}{dt}=\frac{150}{50\pi}=\frac{3}{\pi} m/s$

$\frac{dr}{dt}=\frac{3}{\pi} m/s$

b.A= $1000m^2$

Substitute the values then we get

$1000=\pi r^2$

$\pi=3.14$

$r^2=\frac{1000}{3.14}$

$r=\sqrt{\frac{1000}{3.14}}=17.8m$

$\frac{dA}{dr}=2\pi r\frac{dr}{dt}$

Substitute the values then we get

$150=2\pi(17.8)\frac{dr}{dt}$

$\frac{dr}{dt}=\frac{150}{2\pi(17.8)}=\frac{150}{35.6\pi}$ m/s

$\frac{dr}{dt}=\frac{75}{17.8\pi}$ m/s

4 0

3 years ago

If sin(2x + 7)degrees =cos(4x-7)degrees, what is the value of x?

nikklg [1K]

Answer:

x = 15

Step-by-step explanation:

$cosx = sin(\frac{\pi}{2} - x)$

$sin x = sin y = > x = sin^{-1}(sin y) = y => x = y$

$sin(2x + 7)^{\circ} = cos(4x - 7)^{\circ}\\\\sin(2x + 7)^{\circ} = sin(\frac{\pi}{2} - (4x - 7))\\\\(2x + 7) = (\frac{\pi}{2}- (4x -7))\\\\2x + 7 = \frac{\pi}{2} - 4x + 7\\\\6x = \frac{\pi}{2}\\\\x = \frac{\pi}{12}$

x = 15

8 0

2 years ago