Spreadsheets: Rows, Columns and a Formula That Updates Itself
A spreadsheet holds values in cells and formulas that refer to those cells by name. Change one value and everything computed from it recalculates, which is what makes a sheet a model rather than a table.
What a learner can do afterwards
- Write a formula that refers to cells rather than to numbers typed into the formula
- Change one input and predict, before looking, which cells will change
- Copy a formula down a column and say what happened to the references it contains
1 · Read
A spreadsheet is a model, not just a table. When you plan snacks for a class party, you type a formula into a cell, starting with an equals sign, and the sheet works out the total cost. The whole file is called a workbook, and one grid tab inside it is called a worksheet.
Every formula starts with an equals sign and may name cells, like =A1+A2. Use star for times and slash for divide, with brackets to set order.
A1 holds 4 and A2 holds 7, so =A1+A2 shows 11. Change A1 to 10 and the answer updates to 17 all by itself. Copy that formula down a column and its names shift with it, so one rule prices a whole list.
Copy a formula down a column and its names shift with it. Copying down is how one rule prices a whole list.
Point formulas at cells, not fixed numbers, and the sheet updates itself when inputs change.
2 · Watch
Take it off screen
Where it sits
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.