Math Puzzles Printable For Learning Activity Shelter, 48% OFF - Free Printable

Let's solve this "Secret Code Math" worksheet step by step and explain the solution.

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🔍 Objective:

1. Decode the symbols into numbers using the provided key.
2. Round each decoded number to the nearest ten.

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📌 Step 1: Understand the Code Key

At the top, there is a symbol-to-number code:

| Symbol | Number |
|--------|--------|
| `//` | 1 |
| `/\` | 2 |
| `<` | 3 |
| `>` | 4 |
| `^` | 5 |
| `v` | 6 |
| `<>` | 7 |
| `*` | 8 |
| `)` | 9 |
| `C` | 0 |

> Note: The symbol for 0 is a C, which looks like a curved line (like a parenthesis).

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Now let’s decode each row.

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✔ Row-by-Row Decoding & Rounding

#### Row 1:
- Code: `> *`
- Decode:
- `>` = 4
- `*` = 8
→ 48
- Round to nearest ten:
48 → 50

✔ Matches answer key: 50

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#### Row 2:
- Code: `/\ <`
- Decode:
- `/\` = 2
- `<` = 3
→ 23
- Round to nearest ten:
23 → 20

✔ Matches: 20

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#### Row 3:
- Code: `<> ^`
- Decode:
- `<>` = 7
- `^` = 5
→ 75
- Round to nearest ten:
75 → 80 (since 75 is halfway, we round up)

✔ Matches: 80

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#### Row 4:
- Code: `* v`
- Decode:
- `*` = 8
- `v` = 6
→ 86
- Round to nearest ten:
86 → 90

✔ Matches: 90

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#### Row 5:
- Code: `) >`
- Decode:
- `)` = 9
- `>` = 4
→ 94
- Round to nearest ten:
94 → 90

✔ Matches: 90

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#### Row 6:
- Code: `// /\ <>`
- Decode:
- `//` = 1
- `/\` = 2
- `<>` = 7
→ 127
- Round to nearest ten:
127 → 130 (because 7 ≥ 5, so round up)

✔ Matches: 130

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#### Row 7:
- Code: `/\ v >`
- Decode:
- `/\` = 2
- `v` = 6
- `>` = 4
→ 264
- Round to nearest ten:
264 → 260? Wait — but answer key says 240?

✘ Wait! There’s a mismatch here.

But look again: the answer key shows 264 → 240? That can’t be right.

Let’s double-check:

- 264 rounded to nearest ten:
- Look at the ones digit: 4
- Since 4 < 5, we round down
→ 260

But the answer key says 240 — that’s not correct.

Wait — maybe I misread the code?

Let’s check the code symbols in row 7:

> Code: `/\ v >`

We have:
- `/\` = 2
- `v` = 6
- `>` = 4

So: 264

But the real number in the answer key is 264, and it says 240 as the rounded value.

That’s wrong.

Wait — no, look again: the answer key shows "264" under Real Numbers, and "240" under Rounded.

But 264 → 260, not 240.

So either:
- The answer key has an error, or
- I misread the code.

Let me recheck the symbols in row 7:

The code is: `/\ v >`

Is that really `/\`, `v`, `>`?

Yes.

But maybe the order matters? Could it be a typo?

Wait — perhaps the real number should be 240, not 264?

No — the real number is clearly written as 264.

So rounding 264 to nearest ten is 260, not 240.

But the answer key says 240.

This is a mistake in the answer key.

Let’s move on and see if other rows make sense.

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#### Row 8:
- Code: `v C ^`
- Decode:
- `v` = 6
- `C` = 0
- `^` = 5
→ 605
- Round to nearest ten:
- Ones digit: 5 → round up
→ 610

✔ Matches: 610

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❗ Issue with Row 7

Let’s double-check row 7:

- Code: `/\ v >` → 2, 6, 4 → 264
- Rounded to nearest ten: 264 → 260

But the answer key says 240.

This is incorrect.

Unless... the code symbols are different.

Wait — maybe I misread the symbol.

Look back at the image:

In row 7, the code is: `/\ v >`

But maybe the first symbol is not `/\`, but something else?

Wait — no, it’s clearly two slashes: `//` is 1, `/\` is 2.

And `v` is 6, `>` is 4.

So 264 is correct.

But why does it say 240?

Possibility: Maybe the code is meant to be `/\ v <` instead of `>`?

If it were `<`, then it would be 3, making 263, which rounds to 260 still.

Or if it were `C`, that would be 0.

Wait — maybe the real number is not 264, but 240?

But no — the real number is written as 264.

Alternatively, could the code be interpreted differently?

Wait — maybe the code uses a different mapping?

Let me recheck the key:

| Symbol | Number |
|--------|--------|
| `//` | 1 |
| `/\` | 2 |
| `<` | 3 |
| `>` | 4 |
| `^` | 5 |
| `v` | 6 |
| `<>` | 7 |
| `*` | 8 |
| `)` | 9 |
| `C` | 0 |

All seem consistent.

So unless the code symbols are misread, 264 is correct.

But 264 → 260, not 240.

So the answer key has a mistake in row 7.

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✔ Final Answer Summary

| Code Numbers | Real Numbers | Round to Nearest Ten |
|--------------|--------------|----------------------|
| `> *` | 48 | 50 |
| `/\ <` | 23 | 20 |
| `<> ^` | 75 | 80 |
| `* v` | 86 | 90 |
| `) >` | 94 | 90 |
| `// /\ <>` | 127 | 130 |
| `/\ v >` | 264 | 260 (not 240!) |
| `v C ^` | 605 | 610 |

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⚠️ Conclusion

The only error is in row 7:

- Real number: 264
- Correct rounded value: 260
- But answer key says 240 → This is incorrect.

All other answers are correct.

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✔ Corrected Answer Key

| Code Numbers | Real Numbers | Round to Nearest Ten |
|--------------|--------------|----------------------|
| `> *` | 48 | 50 |
| `/\ <` | 23 | 20 |
| `<> ^` | 75 | 80 |
| `* v` | 86 | 90 |
| `) >` | 94 | 90 |
| `// /\ <>` | 127 | 130 |
| `/\ v >` | 264 | 260 ← CORRECTED |
| `v C ^` | 605 | 610 |

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💡 How to Round to Nearest Ten:

- Look at the ones digit.
- If it’s 5 or more, round up.
- If it’s less than 5, round down.

Examples:
- 48 → 50 (8 ≥ 5)
- 23 → 20 (3 < 5)
- 75 → 80 (5 = 5 → round up)
- 264 → 260 (4 < 5)

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✔ So the correct answer for row 7 is 260, not 240.

Let me know if you'd like a printable version or help creating similar problems!