.....................................

A sphere and a cylinder have the same radius and height. The volume of the cylinder is 21m. what is the volume of the sphere.

Goshia [24]

Answer:

The volume of the sphere is 14m³

Step-by-step explanation:

Given

Volume of the cylinder = $21m^3$

Required

Volume of the sphere

Given that the volume of the cylinder is 21, the first step is to solve for the radius of the cylinder;

Using the volume formula of a cylinder

The formula goes thus

$V = \pi r^2h$

Substitute 21 for V; this gives

$21 = \pi r^2h$

Divide both sides by h

$\frac{21}{h} = \frac{\pi r^2h}{h}$

$\frac{21}{h} = \pi r^2$

The next step is to solve for the volume of the sphere using the following formula;

$V = \frac{4}{3}\pi r^3$

Divide both sides by r

$\frac{V}{r} = \frac{4}{3r}\pi r^3$

Expand Expression

$\frac{V}{r} = \frac{4}{3}\pi r^2$

Substitute $\frac{21}{h} = \pi r^2$

$\frac{V}{r} = \frac{4}{3} * \frac{21}{h}$

$\frac{V}{r} = \frac{84}{3h}$

$\frac{V}{r} = \frac{28}{h}$

Multiply both sided by r

$r * \frac{V}{r} = \frac{28}{h} * r$

$V = \frac{28r}{h}$ ------ equation 1

From the question, we were given that the height of the cylinder and the sphere have equal value;

This implies that the height of the cylinder equals the diameter of the sphere. In other words

$h = D$ , where D represents diameter of the sphere

Recall that $D = 2r$

So, $h = D = 2r$

$h = 2r$

Substitute 2r for h in equation 1

$V = \frac{28r}{2r}$

$V = \frac{28}{2}$

$V = 14$

Hence, the volume of the sphere is 14m³

4 0

3 years ago

Read 2 more answers

If you add 12 to my number and then multiply the result by 3, you will get 64 more than two-thirds of my number. Find my number.

anastassius [24]

Answer:

The number is 12

Step-by-step explanation:

[] First, let's turn all these words into something mathematical. N will equal "my number"

-> If you add 12 to my number and then multiply the result by 3, you will get 64 more than two-thirds of my number.

-> n + 12 and then multiply the result by 3, you will get 64 more than two-thirds of my number.

-> 3(n + 12), you will get 64 more than two-thirds of my number.

-> 3(n + 12) = 64 more than $\frac{2n}{3}$

-> 3(n + 12) = 64 + $\frac{2n}{3}$

[] Phew, okay. Now it is something we can solve and less scary;

[Given]

3(n + 12) = 64 + $\frac{2n}{3}$

[Distribute]

3n + 36 = 64 + $\frac{2n}{3}$

[Multiply both sides by 3]

9n + 108 = 192 + 2n

[Subtract 108 and 2n from both sides]

7n = 84

[Divide both sides by 4]

n = 12

Have a nice day!

I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)

- Heather

8 0

2 years ago

What is the value of the expression

Gelneren [198K]

Answer:32

Step-by-step explanation: First you do 4×4×4×

=64 then you divide by 2.. 64÷2=32

8 0

3 years ago

Read 2 more answers

The first person to answer correctly gets BRAINLIEST!. (20 POINTS)

asambeis [7]

Answer:

y = 288 - 60x

Step-by-step explanation:

6 0

3 years ago

The following examples illustrate the associative property of multiplication.

kati45 [8]

Answer:

A) a • (b • c) = (a • b) • c

Step-by-step explanation:

The associative property of multiplication (or addition) shows that the order the numbers are multiplied it irrelevant, more specifically in the manners of parentheses.

So, the answer is A, which can also be seen in that substituting a as 5, b as 3, and c as 6 gives us the first example.

4 0

2 years ago

Read 2 more answers