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after a 2-inch slice is cut from a rectangular prism, the remaining shape is a perfect cube. find the length of the edge of the cube if the original volume was 175 cubic inches. show your solution is unique.

User Lschin
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Final answer:

The unique length of the edge of the cube after slicing 2 inches from a rectangular prism with an original volume of 175 cubic inches is 5 inches. We confirmed this by solving the equation s^3 + s^2 × 2 = 175, which only holds true for s = 5.

Step-by-step explanation:

The question involves finding the edge length of a cube after slicing 2 inches from a rectangular prism such that the remaining shape is a perfect cube, given the original volume was 175 cubic inches.

Let's denote the edge length of the cube as s.

Since the remaining shape is a cube, the volume is s^3. To find the value of s, we first realize that the volume of the original rectangular prism was the volume of the cube plus the volume of the 2-inch slice. The volume of the slice would be s^2 × 2 inches.

Therefore, the original volume 175 = s^3 + s^2 × 2.

To solve this equation, we can try different integer values for s because we know that both terms in the original volume equation are whole numbers.

By trial and error, if s = 5, then the cube's volume is 125 and the volume of the slice is 50 (5^2 × 2), which adds up to 175 cubic inches - the original volume. This shows that the edge of the cube is 5 inches.

This solution is unique as no other whole number satisfies the volume equation.

User Ashish Goel
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