Spreadsheets for Decisions

Spreadsheets for Real Decisions

Build a worksheet someone can trust, then use it to make and defend a decision.

Times are planning estimates from each lesson's stated length, not measured completion times.

Reading and practice are open to everyone. Saving your progress needs an account with access to this course.

What the practice looks like

Spreadsheets for DecisionsSample from Write and copy formulas

Cost column built from one rate cell: each formula multiplies its own row's learners by the rate in I2
Row	C · Learners	E · Formula	E · Cost
2	18	`=C2*$I$2`	76.5
3	12	`=C3*$I$2`	51
4	21	`=C4*$I$2`	89.25

I2 · Rate per learner: 4.25

The rate lives in one cell. The dollar signs keep every copied row pointing at it.

Modules are in the recommended order, and every lesson is open from day one.

Build a trustworthy worksheet
Lay out data someone else can check, write formulas that survive being copied, and reconcile a total against the rows it came from.
Clean data before deciding
Bring an external file in without losing what it says, tell real duplicates from legitimate repeats, and leave a cleanup trail somebody else can audit.
Compare meaningful groups
Turn a written policy into a tested formula, answer grouped questions with a denominator that matches the question, and attach reference data by key while showing what did not match.
Model costs and alternatives
Build a cost model whose assumptions are visible and changeable, compare alternatives on total cost including the terms that are easy to miss, and show how far the answer moves when the assumptions do.
Communicate an honest result
Summarize by category and period, choose a chart that does not mislead, and assemble a one-screen decision view that states its own limits.
The capstone decision
Assemble a workbook from data nobody has cleaned, compare two ways of buying the same equipment, and deliver a recommendation a stranger can check.