Question

Whats the Diameter? I really need help understanding this

Answer 1

Answer:

1.8 in

Step-by-step explanation:

we know the equation for the volume of a cone is pi*r^2 h/3=3.6

pi r^2 *4.2=10.8

solve for r

r is about 0.9 so diameter is 1.8 in

Answer 2

Answer:

1.8 in.

Step-by-step explanation:

Hi there!

1) Determine the radius of the base

$V=\frac{1}{3} \pi r^2h$ where r is the radius of the base and h is the height of the cone

Plug in the known values (h=4.2, V=3.6)

$3.6=\frac{1}{3} \pi r^2(4.2)$

Isolate r; divide both sides by 4.2

$\frac{3.6}{4.2} =\frac{1}{3} \pi r^2\\\frac{6}{7} =\frac{1}{3} \pi r^2$

Multiply both sides by 3

$\frac{6}{7}*3 =\pi r^2\\\frac{18}{7}=\pi r^2$

Divide both sides by π

$\frac{18}{7\pi }=r^2$

Take the square root of both sides

$\sqrt{\frac{18}{7\pi }} =r$

2) Determine the diameter

Now that we have the radius, to find the diameter, multiply r by 2:

$d=\sqrt{\frac{18}{7\pi }}*2\\d=1.8$

Therefore, the diameter is 1.8 in. when rounded to the nearest tenth.

I hope this helps!