<a id="ch-17"></a>

## Chapter 17 — Fourteen of eighteen is not July

<!-- open-cyber-academy:lesson-figures:start ch-17 -->
### Lesson map

Lesson 17. Map, example, EX063.

```mermaid
flowchart TD
  C["18 cells"] --> O["14 ones"]
  C --> Z["4 zeros"]
  J["July is the only all-ones month"] --> Q{"Did the script print 14/18?"}
  O --> Q
  Q -->|No| K["The print stays three month lines"]
```

A cell total is a further reduction. It is not a line in the output.

### Logical drawing

```text
column ones: sharing 3, admin 3, restore 2, image 1, leavers 3, notices 2
zero cells:  May restore, May image, May notices, June image
printed:     May 3/6, June 5/6, July 6/6
not printed: 14/18, the column sums, a mean
```
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### Learning outcomes

After this chapter, you should be able to:

1. Add the three numerators without replacing the print.
2. Name the four zero cells and the image column.
3. Refuse a single grade for the quarter.

### 17.1 The script prints months. The cell sum is extra arithmetic.

The three numerators are 3, 5, and 6. Their total is 14 ones. Three months times six tasks is 18 cells, so the zeros are 4. Those four positions are May's restore, May's image, May's notices, and June's image. Image is the only task with two zeros. Sharing, the admin check, and leavers are ones in every month. Restore and notices each have a single zero, both in May.

July is the only key for which every cell is `1`. That is one month's conjunction. It is not a property of the eighteen cells. The program never prints `14/18`, never prints the column sums, and never prints an average of the three numerators. A note that replaces the three lines with one of those figures is reporting a quantity the output did not contain. The derivation can be shown beside the print. It must not be pasted over it.

One person recorded the ticks. No second rater is described, so no agreement coefficient is available. August is not a key in the dictionary.

### 17.2 Worked example

| Figure | Status | Decision |
|---|---|---|
| May 3/6, June 5/6, July 6/6 | Printed | Keep |
| 14 ones and 4 zeros | Derived, not printed | May be shown as a derivation |
| "The quarter score is 14/18, so July is the file." | Replaces the three lines | Reject |
| "Image passed every month." | The column has two zeros | Reject |

> **Synthetic case.** The derivation sits beside the embedded lines. It does not edit them.

### Errors and limits

Do not average 3, 5, and 6 into a grade the deputy could mistake for the print.

### Apply

- **EX063 — Beside, not over.** A summary replaces the three month lines with 14/18, says the image column passed, and calls July the whole result. What do you keep, and what may be mentioned only as arithmetic beside the file? *Rubric:* 3 = keep the three printed lines; 14 ones and 4 zeros may be derived and must not replace the print; image is 1 of 3; July is the only all-ones month;; 2 = the printed lines stay and 14/18 is not the file;; 1 = one line;; 0 = none.

<!-- open-cyber-academy:chapter-navigation:start ch-17 -->
### Continue studying — lesson 17 (chapter 17 of 20)

[← Chapter 16](#ch-16) · [Course chapter index](../SUBJECTS.md) · [Chapter 18 →](#ch-18)

Continue to the next authored lesson.
<!-- open-cyber-academy:chapter-navigation:end -->

## Worked answers

<a id="answer-ex063"></a>
**EX063.** Keep May 3/6, June 5/6, and July 6/6. Fourteen ones and four zeros may be derived beside the print and must not replace it. The image column is 1 of 3. July is the only all-ones month.
