Artificial Intelligence / Unit 6 AI 0302 worked example, 60 to 90 seconds
Same Answer, Two Roads
The idea
Running the screening problem by formula reproduces the count to the digit — because the formula is the count with the thousands canceled.
In practice
The three quantities, read off the story. Likelihood: the test flags carriers at 0.9. Prior: 4 percent carry — 0.04. Evidence overall: both routes to a flag, multiply-along and add-across — 0.9 × 0.04 plus 0.1 × 0.96, which is 0.036 plus 0.096: 0.132. Divide: 0.036 over 0.132 — 3 in 11, the same 27 percent the room count gave. Line the roads up side by side: 36-in-a-thousand over 132-in-a-thousand, thousands canceled, is exactly 0.036 over 0.132. Two notations, one count — and whichever you run, the base rate sits inside the arithmetic where it cannot be forgotten.
Where people slip
A formula term misplaced fails silently; a room miscounted fails visibly — which is why the count is the anchor skill.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
- Nothing yet depends on this.
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