The changed object: Rosetta Stone
The correct adjustment: 1.6× the original shown size.

Jaques Hurlingham croquet mallet measures about 95 cm; this comparison uses the approximate total length from the top of the handle to the bottom of the head, shown upright.
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Burgon & Ball BoronGreen digging fork measures 1.1 m; this comparison uses the overall length from the lowest tine tips to the top of the Y-shaped handle, shown upright.
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For Rosetta Stone, British Museum records 112.3 cm tall: Named granodiorite slab upright, bottom edge to highest surviving top; no display base.
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For Drive Nitro RTL10266 rollator, Drive Medical specifies 97.155 cm: ground-to-handle height at the maximum setting, with the rollator unfolded; converted from 38.25 inches.
SourceIllustrations shown individually, not to a shared scale.