Ask question

Ask question

All categories

Aleksandr-060686 [28]

2 years ago

6

You are working for a company that creates tubes that measure 10 cm long and have a diameter of 6 cm. The tubes need to be cut j

ust right. The company fired all of its math people so they do not know how to calculate the size of the tube needed. Please calculate the surface area needed for the tube. Use 3.14 for pi. *

1 answer:

Nataly_w [17]2 years ago

4 0

Answer:

$A= 2\pi (3cm)^2 +1 2\pi (3cm)(10 cm)= 18 \pi + 60\pi = 78 \pi cm^2$

And replacing the value of $\pi =3.14$ we got:

$A = 78*3.14 cm^2= 244.92 cm^2$

Step-by-step explanation:

For this case we have the long who represent the height 10 cm and the diameter is 6cm. So then the radius is given by:

$r = \frac{D}{2}= \frac{6cm}{2}= 3cm$

And the surface area for a cylinder is given by this formula:

$A= 2\pi r^2 +2 \pi rh$

And replacing the info given we got:

$A= 2\pi (3cm)^2 +1 2\pi (3cm)(10 cm)= 18 \pi + 60\pi = 78 \pi cm^2$

And replacing the value of $\pi =3.14$ we got:

$A = 78*3.14 cm^2= 244.92 cm^2$

You might be interested in

Match the circle equations in general form with their corresponding equations in standard form. Not all will be used.

Xelga [282]

<span>The standard form of the equation of a circumference is given by the following expression:

</span> $(x-h)^{2}+(y-k)^{2}=r^{2} \\ \\ where \ (h, k) \ is \ the \ center \ of \ the \ circumference \ and \ r \ the \ radius$
<span>
On the other hand, the general form is given as follows:

</span> $x^{2}+y^{2}+Dx+Ey+F=0 \\ \\ where: \\ D=-2h, \ E=-2k, \ F=h^{2}+k^{2}-r^{2}$ <span>

In this way, we can order the mentioned equations as follows:

Equations in Standard Form:

</span> $\bold{a)} \ (x-6)^{2}+(y-4)^{2}=56 \\ \bold{b)} \ (x-2)^{2} + (y+6)^{2}=60 \\ \bold{c)} \ (x+2)^{2}+(y+3)^{2}=18 \\ \bold{d)} \ (x+1)^{2}+(y-6)^{2}=46$

Equations in General Form:

$\bold{1)} \ x^{2}+y^{2}-4x+12y-20=0 \\ \bold{2)} \ x^{2}+y^{2}+6x-8y-10=0 \\ \bold{3)} \ 3x^{2}+3y^{2}+12x+18y-15=0 \\ \\ If \ we \ divide \ this \ equation \ by \ 3, \ the \ equation \ becomes: \\ x^{2}+y^{2}+4x+6y-5=0 \\ \\ \bold{4)} \ 5x^{2}+5y^{2}-10x+20y-30=0 \\ \\ If \ we \ divide \ this \ equation \ by \ 5, \ the \ equation \ becomes: \\ x^{2}+y^{2}-2x+4y-6=0 \\ \\ \bold{5)} \ 2x^{2}+2y^{2}-24x-16y-8=0 \\ \\ If \ we \ divide \ this \ equation \ by \ 2, \ the \ equation \ becomes: \\ x^{2}+y^{2}-12x-8y-4=0$

$\bold{6)} \ x^{2}+y^{2}+2x-12y$

So let's match each equation:

$\bold{From \ a)} \\ \\ (h,k)=(6,4),\ r=2\sqrt{14} \\ D=-12, \ E=-8 \\ F=-4$

Then, its general form is:

$x^{2}+y^{2}-12x-8y-4=0$

<em><u>First. a) matches 5) </u></em>

$\bold{From \ b)} \\ \\ (h,k)=(2,-6),\ r=2\sqrt{15} \\ D=-4, \ E=12 \\ F=-20$

Then, its general form is:

$x^{2}+y^{2}-4x+12y-20=0$

<em><u>Second. b) matches 1) </u></em>

$\bold{From \ c)} \\ \\ (h,k)=(-2,-3),\ r=3\sqrt{2} \\ D=4, \ E=6 \\ F=-5$

Then, its general form is:

$x^{2}+y^{2}+4x+6y-5=0$

<em><u>Third. c) matches 3)</u></em>

$\bold{From \ d)} \\ \\ (h,k)=(-1,6),\ r=\sqrt{46} \\ D=2, \ E=-12, \ F=-9$

Then, its general form is: $x^{2}+y^{2}+2x-12y-9=0$

<em><u>Fourth. d) matches 6)</u></em>

6 0

3 years ago

Read 2 more answers

If (x - 4) varies inversely as (y + 3) and x = 8 when y = 2, what is x when y = - 1?

denpristay [2]

Answer:

$x=14$

Step-by-step explanation:

If two values are inversely proportional, their product must be maintained. That way, if one value goes up, the other goes down by the same extent.

Therefore, if $(x-4)$ and $(y+3)$ vary inversely, their product will be the same for all values of $x-4$ and $y+3$ .

Let $x=8$ and $y=2$ as given in the problem. Substitute values:

$(8-4)(2+3)=(4)(5)=20$

Hence, the maintained product is $20$ .

Thus, we have the following equation:

$(x-4)(y+3)=20$

Substitute $y=-1$ to find the value of $x$ when $y=-1$ :

$(x-4)(-1+3)=20,\\(x-4)(2)=20,\\x-4=10,\\x=10+4=\boxed{14}$

3 0

2 years ago

What is the reason for #2?

NeTakaya

Answer:

I am not sure but i will say C.

Step-by-step explanation:

3 0

2 years ago

What is continuous compounding? how does the apy for continuous compounding compare to the apy for, say, daily compounding? e

aliya0001 [1]

Continuous compounding is the mathematical limit that compound interest can reach.

It is the limit of the function A(1 + 1/n) ^ n as n approaches infinity. IN theory interest is added to the initial amount A every infinitesimally small instant.
The limit of (1 + 1/n)^n is the number e ( = 2.718281828 to 9 dec places).

Say we invest $1000 at daily compounding at yearly interest of 2 %. After 1 year the $1000 will increase to:-

1000 ( 1 + 0.02/365)^365 = $1020.20

with continuous compounding this will be

1000 * e^1 = $2718.28

4 0

2 years ago

Read 2 more answers

Find cos 0.<br> 53<br> 45<br> 28

Lemur [1.5K]

The answer is A. 28/53

4 0

2 years ago