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What is the volume of a rectangular prism that is 1 1/2 inches by 2 1/4 inches by 4 inches? SHow your reasoning.

User Peet
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1 Answer

10 votes

Answer:

27/2 in^3 or 13.5 in^3 as a mixed fraction

Explanation:

V=whl

Simplify the following:

(1 + 1/2) (2 + 1/4)×4

Put 1 + 1/2 over the common denominator 2. 1 + 1/2 = 2/2 + 1/2:

(2/2 + 1/2) (2 + 1/4)×4

2/2 + 1/2 = (2 + 1)/2:

((2 + 1)/2) (2 + 1/4)×4

2 + 1 = 3:

3/2 (2 + 1/4)×4

Put 2 + 1/4 over the common denominator 4. 2 + 1/4 = (4×2)/4 + 1/4:

(3×4)/2 ((4×2)/4 + 1/4)

4×2 = 8:

(3 (8/4 + 1/4)×4)/2

8/4 + 1/4 = (8 + 1)/4:

(3×4)/2 ((8 + 1)/4)

8 + 1 = 9:

3/2×9/4×4

3/2×9/4×4 = (3×9×4)/(2×4):

(3×9×4)/(2×4)

(3×9×4)/(2×4) = 4/4×(3×9)/2 = (3×9)/2:

(3×9)/2

3×9 = 27:

Answer: 27/2 or 13.5 as a mixed fraction

User Tuyen
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