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Question 1 In the figure, the cube and the cylinder have equal volume. If two sides of the cube are doubled, and the diameter of the cylinder is doubled, will the volumes of the resulting prisms still be equal? Show all calculations. 1.1 (5)​

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let's see, assume the cube is 4" on a side with a vol of 64

let r = h then volume of the cylinder:

find r, the cube root of 64/pi

r = 

r = 2.73", diameter = 5.46

"If two sides of the cube are doubled,and the diameter of the cylinder is doubled"

8*8*4 = 256 cu/in

 = 255.68 ~ 256, I guess we could call them equal

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User Marcel Toth
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The volumes of the resulting prisms will not be equal. The cube's volume will be double the cylinder's volume after these modifications.

**Current scenario:**

- Let the side length of the cube be `s` and the radius of the cylinder be `r`.

- Volume of the cube: `V_cube = s^3`

- Volume of the cylinder: `V_cylinder = πr^2h` (assume cylinder height remains the same)

**Scenario 1: Doubling two sides of the cube:**

- New side length of the cube: `2s`

- New volume of the cube: `V_cube_new = (2s)^3 = 8s^3`

**Scenario 2: Doubling the diameter of the cylinder:**

- New diameter: `2d = 2 * 2r = 4r`

- New radius: `r_new = d/2 = 4r/2 = 2r`

- New volume of the cylinder: `V_cylinder_new = π(2r)^2h = 4πr^2h`

**Comparing new volumes:**

- Ratio of new cube volume to old cube volume: `V_cube_new / V_cube = 8s^3 / s^3 = 8`

- Ratio of new cylinder volume to old cylinder volume: `V_cylinder_new / V_cylinder = 4πr^2h / πr^2h = 4`

Conclusion:

- The volume of the cube increases by a factor of 8 when two sides are doubled.

- The volume of the cylinder increases by a factor of 4 when the diameter is doubled.

Therefore, the volumes of the resulting prisms will not be equal. The cube's volume will be double the cylinder's volume after these modifications.

User Yuridiana
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