Math question: A round cylindrical water tank 10 m high..?

Question

A round cylindrical water tank 10 m high has a volume of 125.6 m3 (meters cubed). Find the diameter of the tank.

Could you show me HOW it is done too? Thanks.

Answer 1

The formula for the volume of a cylinder is:

Volume = Pi * radius^2 * height

which I'll rephrase as:

V = P*r^2*h

Start plugging in the values that you know:

125.6 = 3.14 * r^2 * 10

Simplify:

125.6 = 31.4 * r^2

125.6/31.4 = (31.4*r^2)/31.4

4 = r^2

sqrt(4) = sqrt(r^2)

2 = r.

The radius is 2m.

Answer 2

Firstly the formula for calculating the volume of a cylinder is

Pi x r(squared) x H(height)

So if the height is 10 metres then the area of the cross section circle is 125.6 divided by 10
= 12.56 sqm
Therefore Pi x r (squared) = 12.56
so r (squared) = 12.56 / Pi
we know that Pi= 3.14159
so r(squared) = 12.56/ 3.14159
so r (sqd)= 3.9979 or 4
so r = the sq root of 4
so therefore r=2 metres

Answer 3

The formula for the volume of a cylinder is:

Volume = Pie, radius square, height

which I'll rephrase as:

V = P*r^2*h

Start plugging in the values that you know:

125.6 = 3.14 * r^2 * 10

Simplify:

125.6 = 31.4 * r^2

125.6/31.4 = (31.4*r^2)/31.4

4 = r^2

sqrt(4) = sqrt(r^2)

2 = r.

so tht means
d= 2r
d=2x2
d=4

Answer 4

volume = (area of base of cylinder)(height of cylinder)
volume = (pi*radius^2)(10)
125.6 = 10pi*r^2; divide both sides by 10pi
4 = r^2
2 = r

(I rounded pi to 3.14 because your teacher did too to make the math easier).

Since the radius = 2 m, the diameter = 4 m (d = 2r)

Answer 5

pi*(d^2/4)*h=volume
plugging the values
3.14*(d^2/4)*10=125.6
d^2=125.6(4)/31.4
=16
therefore d=(16)^1/2=4