Test Lab · Infographic
Four sides around one mean
See which reconstructed Great Pyramid sides fall above and below Petrie’s mean.
East falls furthest from the reconstructed mean
The middle line marks Petrie’s 9,068.8-inch mean. The chart magnifies differences around it in millimetres using 25.4 mm per inch.
Read the four values
| Side | Difference (in) | Approx. difference (mm) |
|---|---|---|
| North | +0.6 | +15.2 |
| East | −1.1 | −27.9 |
| South | +0.7 | +17.8 |
| West | −0.2 | −5.1 |
The mean has its own reported error
Petrie gives 9,068.8 ± 0.5 inches for the mean used in his height calculation. The ±0.5 inches is his probable error for that mean. Each bar instead shows how far one reconstructed side lies from the mean.
W. M. Flinders Petrie, The Pyramids and Temples of Gizeh (1883), pp. 39–40, 43. Read the source and rounding discussion.
Visual reference: Flint for anchoring signed values to a labelled baseline.