There are two equal bottomed cylinders. The height of the first cylinder is 45 times that of the second cylinder. The volume of the first cylinder is 3.2 cubic centimeters. How many cubic centimeters more is the second cylinder than the first one?

There are two equal bottomed cylinders. The height of the first cylinder is 45 times that of the second cylinder. The volume of the first cylinder is 3.2 cubic centimeters. How many cubic centimeters more is the second cylinder than the first one?


Let the volume of the second cylinder be x cubic centimeter, 4:5 = 3.2: X, & nbsp; 4x = 3.2 × 5, & nbsp; 4x = 16, & nbsp; & nbsp; X = 4; 4-3.2 = 0.8 (cubic centimeter); answer: the volume of the second cylinder is 0.8 cubic centimeter more than that of the first one



A part with a bottom diameter of 5 cm and a height of 10 cm is cut down along one of its bottom diameters and cut into two parts of the same size. How many square centimeters is the total area increased from the original? (2) What is the surface area of each half part? What's the volume?


(1) 10 × 5 × 2 = 100 (square centimeter); answer: the total area is increased by 100 square centimeter; (2) [3.14 × (5 △ 2) 2 × 2 + 3.14 × 5 × 10] △ 2 + 10 × 5, = 98.125 + 50, = 148.125 (square centimeter); 3.14 × (5 △ 2) 2 × 10 △ 2, = 196.25 △ 2, = 98.125 (cubic centimeter); answer: the surface area of each half part is 148.125 square centimeter, and the volume is 98.125 cubic centimeter



The sum of the volumes of a cylinder and a cone is 130 cubic centimeters. The height of a cone is twice that of a cylinder. The area of the bottom of a cone is 23 times that of a cylinder. How many cubic centimeters are the volumes of a cylinder and a cone?


Let the height of the cylinder be h, then the height of the cone be 2h, the area of the bottom of the cylinder be 3S, then the area of the bottom of the cone be 2S, so the volume of the cylinder is 3SH, and the volume of the cone is: 13 × 2S × 2H = 43sh, because: 3SH + 43sh = 130, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 9sh + 4sh = 390, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 13SH = 390, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; &So the volume of cylinder is 3 × 30 = 90 (cubic centimeter) and that of cone is 43 × 30 = 40 (cubic centimeter). A: the volume of cylinder is 90 cubic centimeter and that of cone is 40 cubic centimeter