5 1/2 x 1 x 2 1/2

\(5\dfrac{1}{2}\times 1 \times 2\dfrac{1}{2}\\ =\dfrac{11}{2}\times 1 \times \dfrac{5}{2}\\ =\dfrac{11\times 1 \times 5}{2\times 2}\\ =\dfrac{55}{4}\\ =13.75\)

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