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Pear Shape Estimation
Length-to-width adjustments (LWA) for weight estimation formula.
| L/W ratio | LWA |
| 1.25/1.00 | .00615 |
| 1.50/1.00 | .00600 |
| 1.66/1.00 | .00590 |
| 2.00/1.00 | .00575 |
Pear Shape Formula: Length x Width x Depth x LWA x GTA
1) Example of formula in use:
Length measurement: 7.35 mm
Width measurement: 5.20 mm
Depth measurement: 3.05 mm
Girdle: Thick
High shoulders: 1.02
L/W ratio: 7.35 divided by 5.20 = 1.413
Formula will read:
7.35 x 4.89 x 3.25 x .0060 (LWA) x 1.03 (GTA) x 1.02 shape adjustment (high shoulders) = 0.736 Rounded down to 0.73 ct.
2) Example of formula in use:
Length measurement: 9.73 mm
Width measurement: 7.26 mm
Depth measurement: 5.01 mm
Girdle: Very Thick
High shoulders: 1.02
L/W ratio: 9.73 divided by 7.26 = 1.34
Formula will read:
9.73 x 7.26 x 5.01 x .0061 (LWA) x 1.045 (GTA) x 1.02 (shape adjustment, high shoulders) = 2.301 Rounded to 2.30 ct.
