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How to do the problem of cutting off the remaining volume of a small cone in a cone The poem goes like this: on a cone with a bottom radius of 6 decimeters, cut off a cone with a bottom radius of 3 decimeters. The known cut off part is the volume of 27 cubic decimeters
Using the volume ratio to calculate the position from the known volume, the volume ratio can be transformed into height ratio, bottom radius / diameter / area ratio and other solutions: Note: R is the radius of large cone, R is the radius of small cone, h is the height of large cone, h is the height of small cone, V is the volume of large cone, V is the volume of small cone, the basic unit is decimeter known: r = 6, r = 3R / r = H / h
The height of the cone is 36 cm, the height of the cylinder is several cm? A.72 b.36 c.24 d.12
d
Assuming a volume of 240 cubic centimeters, then
The bottom area is 240 × 3 △ 36 = 20 (square centimeter)
So 240 △ 20 = 12 (CM)
Choose D
A question about the principle of drawer
The total score of Congcong's six units is 547, and the highest score of Honghong's six units is 92. Cong Cong said, "I scored no less than you at least once. Can you tell me why?
Because the score of 6 units is regarded as 6 drawers, 574 points is the objects put in the drawer, and the number of objects is greater than the number of drawers. According to the principle of drawers, 574 is divided by 6 quotient 95, 495 + 1 = 96, and 96 is greater than 92, so Congcong's score is no less than Honghong's at least once
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