Dog pregnancy length and why counting from mating widens the due date
A dog's pregnancy averages about 63 days counted from ovulation, but how wide the window is depends on which event start...
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The usual mid-parental height range missed 12% of Galton's grown children
The usual target height averages the parents' heights, shifts the result 6.5 cm for sex and allows 8.5 cm either side. I...
Japan's new kanji forms coincide with the mainland's in about a third of pairs
Japan fixed simpler print forms for its everyday kanji in 1949, and the 2010 Jōyō list still prints an old Kangxi form b...
Descriptive and algebraic chess notation, and the rules FIDE and PGN files disagree on
Old chess books write moves in descriptive notation, naming each square from the mover's side, while FIDE's Laws recogni...
Rebar weight by the d²/162 rule runs a fraction heavy against the standards
Rebar mass per metre is usually worked out as the bar's diameter in millimetres, squared, divided by 162. We checked tha...
Hundreds of subject combinations can add up to the same PSLE Score
Singapore's PSLE Score adds four Achievement Levels into a total from 4 to 32, where lower is better, and MOE sorts thos...
An X chromosome comes from fewer ancestors than a family tree allows
A man's X chromosome can come only from his mother's side, while a woman's comes from both parents, so the ancestors who...
Singapore's golf tees turn one handicap index into very different stroke counts
A Course Handicap rescales a golfer's Handicap Index by the Slope Rating of the tee being played. Across the 88 tees the...
Over a third of a Hokkien dictionary's syllables change between Pe̍h-ōe-jī and Tâi-lô
Pe̍h-ōe-jī (POJ) and Tâi-lô are two ways of writing Hokkien in Latin letters, and Tâi-lô is the scheme Taiwan's Ministry...
Shortcut WBGT formulas land on both sides of Singapore's measured heat stress
Singapore's official heat stress readings blend three thermometers, one of them in the sun. Checked against 30 MSS stati...
Mainland and Taiwan telegraph codebooks nearly always give a Hong Kong ID card character the same code below 8000
The four-digit groups under a Chinese name on a Hong Kong identity card are telegraph codes, which the Immigration Depar...
Singapore, Malaysia and Hong Kong codes set stair risers lower than a US layout assumes
Singapore's Fire Code and Hong Kong's Fire Safety Code limit risers in their escape stairs to 175 mm, and Malaysia's bui...
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