The big idea
🪓
Too large to hold, so cut it
Decomposition works around a hard limit on working memory — and reveals which part actually matters.
Problem Solving & Decision Making · Lesson 2
Breaking Problems into Smaller Parts
beginner⏱ 17 min · 7 cards
Try it
Split It
“Revenue down: fewer customers, or less revenue per customer?”
Does this decomposition pass the MECE test?
Test each decomposition for overlaps and gaps.
Compare
The MECE test
Overlapping
Branches share cases
Tap.
tap for example ↻
Gaps
Branches miss cases
Tap.
tap for example ↻
Ask: could one thing land in two branches? Does anything fall between them?
Key term
Where to start
Which branch first?
tap to reveal ↻
Large and tractable
Size it — what share of the gap does it represent? Then ask what you can actually affect. A branch worth 3% is rarely worth starting on.
Nuance
Check first
Maester Note
The slowest step sets the pace. If 35 of 40 seconds are one payment call, a faster interface is invisible to the user.
Quick check
What three components make something a problem?
You did it
Nice work
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