TL;DR

  • On 8 November The Ledger, the Halfsies guides page, published a guide to estimating a cow's weight with a tape and one formula.
  • The formula squares the chest girth because weight sits in the depth of an animal, not in its outline.
  • Halfsies scores the same thing: a cut is judged by the weight of each half, and the weight comes from drawn area, so a long thin handle counts for very little.
  • Estimation guides bring in people who already like guessing sizes, which is who the game is for.

Halfsies is my daily cutting game. You get three hand-drawn objects a day, cut each one by eye, and a scale weighs the two halves. This morning its guides page put up an article on weighing a cow without a scale. That sounds like a strange subject for a puzzle game, so here is why it belongs there.

The Halfsies guide How to Estimate a Cow's Weight Without a Scale, opening with its one-line answer: multiply heart girth by heart girth by body length in inches and divide by 300
The cow guide on The Ledger, 8 November.

The formula

The guide gives a one-line answer first. Measure the heart girth, the tape around the chest just behind the front legs, and the body length from the point of the shoulder to the pin bone. Multiply girth by girth by length and divide by 300. The answer is in pounds.

Its worked example is a cow 72 inches around and 66 inches long: 72 times 72 times 66, divided by 300, is about 1,140 pounds. Add six inches of girth and the estimate jumps by 250 pounds or more, which is why the guide spends a whole section on taking a clean measurement.

Why the girth gets squared

Girth stands in for the animal's cross section, which is an area, and length stretches that area into a volume. The guide's point is that the eye reads size from the outline, how tall and long an animal looks, while the weight sits in the depth of the chest. A tall, narrow heifer looks heavy. A short, deep cow looks light. The tape corrects for both.

It is the same problem as the game

That is exactly what Halfsies tests. Your score is the lighter half divided by the heavier half, times 100, and the weight of each half comes from the drawn area of the object. A long thin handle counts for very little and a fat body counts for a lot. People cut through the middle of the outline and miss, for the same reason they guess the tall heifer heavy.

The guide makes that link itself near the end and sends readers to the game. I like it more than a list of ten puzzle apps, because it teaches the skill first. The Halfsies ad diary #10 covers what else happened today, including a new verification banner on the ad account.

The Ledger on 8 November, with the cow guide and a list of daily games for couples at the top
The Ledger on 8 November. Two new guides went up that morning.

Why estimation topics

The Ledger has run two guides a day since 29 October, 38 so far, and the ninth diary explains why: the $200 Meta test ended and search costs nothing to keep. The estimation guides, distance by eye, jelly beans in a jar, a pie cut into five and now a cow, reach people who already enjoy guessing sizes. A Western cattle question also fits a game whose ads star a sheriff and a courtroom.

Whether search sends those readers to the game will take weeks to show. For now the cow guide is a good answer to a real question, and that is the bar every guide has to clear.

The cow guide is on The Ledger, and the game is at halfsies.jejestudios.com.

Play Halfsies free on iPhone or on Android.