the formula for the volume of a cone is v=1/3pir^2. find the radius to the nearest hundredth, of a cone with a hieght of 5 inches and a volume of 20inches^3 .
v = (1/3)πr²h
substitute the values you know for the variables in the equation and solve for r.
20 = v
pi = 3.14
h = 5
20 = (1/3)πr²5
solve for r
The answer is 1.95 in
The volume (V) of the cone is:
V = 1/3 π r² h
r - radius
h - height
π = 3.14
It is given:
V = 20 in³
h = 5 in
r = ?
So, let's replace this in the formula for the volume of the cone:
20 = 1/3 π r² 5
Multiply both sides of the equation by 3:
20 3 = 3 1/3 π r² 5
60 = π r² 5
⇒ r² = 60/(π5) = 60/(3.14*5) = 60/15.7 = 3.82
⇒ r = √3.82 = 1.95 in