A solid toy is in the form of a right circular cylinder with a hemisph...
A solid toy is in the form of a right circular cylinder with a hemisph...
To find the volume of the toy, we need to find the volumes of the cylindrical, hemispherical, and conical parts separately and then add them together.
1. Volume of the Cylinder:
The formula for the volume of a cylinder is V = πr²h, where r is the radius and h is the height. Since the diameter is given as 4.2 cm, the radius (r) is half of that, which is 2.1 cm. The height (h) is given as 12 cm. Substituting these values into the formula, we get:
Vcylinder = π(2.1 cm)²(12 cm)
Vcylinder ≈ 166.32 cm³
2. Volume of the Hemisphere:
The formula for the volume of a hemisphere is V = (2/3)πr³, where r is the radius. Since the diameter is given as 4.2 cm, the radius (r) is half of that, which is 2.1 cm. Substituting this value into the formula, we get:
Vhemisphere = (2/3)π(2.1 cm)³
Vhemisphere ≈ 24.572 cm³
3. Volume of the Cone:
The formula for the volume of a cone is V = (1/3)πr²h, where r is the radius and h is the height. Since the diameter is given as 4.2 cm, the radius (r) is half of that, which is 2.1 cm. The height (h) is given as 7 cm. Substituting these values into the formula, we get:
Vcone = (1/3)π(2.1 cm)²(7 cm)
Vcone ≈ 10.972 cm³
4. Total Volume:
To find the total volume of the toy, we add the volumes of the cylindrical, hemispherical, and conical parts together:
Vtotal = Vcylinder + Vhemisphere + Vcone
Vtotal ≈ 166.32 cm³ + 24.572 cm³ + 10.972 cm³
Vtotal ≈ 201.864 cm³
Since the volume of the toy is approximately 201.864 cm³, the closest option is 218 cm³ (option D).