One truth in a table

Chat lies. A workbook recalculates.

A classmate writes “the average is 1.6”. You have 1.8 in the workbook. Who is right? The one where the formulas live.

That is why numbers are not copied into chat, into Word and into another table “just in case”. Every copy gets old. Change one grade — chat still holds 1.6. The workbook shows 1.8. The fight is pointless. The source is one.

One workbook stays. People get a link (right view) or a PDF from today. A PDF is a snapshot. A workbook is the truth that moves. You can do both. You know when which.

That is the Workbook boss: not more functions, but order.

Where the truth lives

Every number has a home. Other places only look at it.

• Grades live on Znamky. The average in one cell under the table.
• Pocket money lives on Kapesne. SUM and levers F1, F2 there.
• Subject names live on Ciselnik. Znamky pulls them with a formula.
• The dashboard owns nothing. It only shows =Znamky!B8 and =Kapesne!C10.

When you fix a grade, you fix it on Znamky. Not on the dashboard. Not in chat. Not in last week’s PDF.

When you fix the name Maths → Mathematics, you fix it in the lookup list. Not in three workbooks.

When you want a different reserve, you move F1. You do not copy the sheet.

A link between sheets is that truth

=Znamky!B8 on the dashboard is not a copy. It is a window. The window shows what is in B8 now.

When from B8 you make =PRŮMĚR(B2:B7) instead of B2:B6, the dashboard shows the new number itself. You do not have to look for it. That is why the average is calculated once, on Znamky, and the dashboard only shows.

The same with the lookup list: =XLOOKUP(D2;Ciselnik!A:A;Ciselnik!B:B) is a window into the list. The name does not live in two places.

When you break this — average on Znamky and by hand on the dashboard and in Word — you have three truths. In a week three different numbers. The Workbook boss leaves one.

The same rule between sheets: do not add on the dashboard again =SUMA(Kapesne!C2:C8) when SUM already lives on Kapesne. Two formulas, two ranges, two results after inserting a row. One total, one link.

Checklist at the end of the course

Go through the workbook like a stranger. Tick only what you actually see.

• Sheets have names (Znamky, Kapesne, Dashboard, Ciselnik), not Sheet1.
• Headings bold, columns readable. Row 1 is a sign.
• Grades and crowns are numbers, not text 2 or 50 Kč by hand.
• Average and SUM reach the right range. Not B:B including the label.
• The chart has a human title, not Chart 1. The average is not in the chart.
• The dashboard shows links, not numbers rewritten by hand. In the formula bar there is =.
• KDYŽ / filter / dollar, if you made them, reach only data rows.
• Sharing is not “anyone edits”. Teacher view, or a PDF.

If one box does not pass, fix it now. The course ends with order, not a new function.

1. Open Dashboard. Say out loud three numbers: average, total, maximum.

2. At each one click B. In the formula bar there must be a link to another sheet. If there is a bare number, delete it and tap the source.

3. Change one grade. Come back to the dashboard. The average moves. The chart moves. You did not edit the dashboard.

4. Open Share. There is not Anyone + Editor. If there is, lower it.

Hand in the source, not a copy

The teacher wants to see that it calculates. A PDF of the dashboard shows numbers. A link with the view right shows that they move. Both are fine. Chat with “I have average 1.8” is not a hand-in.

When you send a PDF, name it dashboard-march.pdf. When you send a link, write in the message which sheet to look at.

Leave raw data in the workbook. Do not delete Znamky “to make it cleaner”. A dashboard without a source is a poster. A poster does not recalculate.

Now you 💪

The last two jobs of the course.

First: open Dashboard. Say out loud three numbers and where they fall from. “1.8 from Znamky B8. 95 Kč from Kapesne C10. Maximum from MAX on column C.” If you can change some number only by rewriting it on the dashboard, it is not a link — fix it.

Second: go through the checklist above. What is not ticked, fix. Then decide how you hand it in: PDF, or a view link. Not chat.

When it fits, you have a workbook that calculates, filters, shows a chart and has one truth. When someone asks you for the average, do not say a number from your head. Open Dashboard. There is a window into B8.

What to take from this lesson

• One table is the source. A copy in chat is the past.
• The dashboard shows. Data lives on sheets. A link =Sheet!Cell holds the truth together.
• The Workbook boss watches order, not just formulas. Share the least rights that are enough.

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