Math worksheet with integer problems and a riddle about a heart-themed sheep.

Let's solve this step-by-step.

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Part 1: Solve the Integer Problems

We are given a series of addition and subtraction problems involving integers. Let's solve each one:

#### A. Addition & Subtraction Problems

1. 4 + (-12) =
→ 4 - 12 = -8

2. -1 + (-2) =
→ -1 - 2 = -3

3. 8 + (-5) =
→ 8 - 5 = 3

4. -4 + 3 =
→ -4 + 3 = -1

5. -3 - 8 =
→ -3 - 8 = -11

6. -7 + (-1) =
→ -7 - 1 = -8

7. 7 + (-4) =
→ 7 - 4 = 3

8. 6 + (-10) =
→ 6 - 10 = -4

9. -20 + 12 =
→ -20 + 12 = -8

10. -1 + (-3) =
→ -1 - 3 = -4

11. 13 + (-3) =
→ 13 - 3 = 10

12. -11 + 5 =
→ -11 + 5 = -6

13. 6 + (-3) =
→ 6 - 3 = 3

14. -16 + 15 =
→ -16 + 15 = -1

15. -3 + (-10) =
→ -3 - 10 = -13

16. -7 + (-8) =
→ -7 - 8 = -15

17. -8 + (-4) =
→ -8 - 4 = -12

18. -8 + 5 =
→ -8 + 5 = -3

19. -2 + 10 =
→ -2 + 10 = 8

---

Now, let's list all the answers:

| Problem | Answer |
|--------|--------|
| A | -8 |
| B | -3 |
| C | 3 |
| D | -1 |
| E | -11 |
| F | -8 |
| G | 3 |
| H | -4 |
| I | -8 |
| J | -4 |
| K | 10 |
| L | -6 |
| M | 3 |
| N | -1 |
| O | -13 |
| P | -15 |
| Q | -12 |
| R | -3 |
| S | 8 |

---

Part 2: Match Answers to Letters in the Riddle

Below is a grid with numbers and letters. We need to match the answers from above to the corresponding numbers in the grid to reveal the riddle’s answer.

The grid looks like this (reconstructed):

```
-16 -18 -3 9 -1
------------------------
13 -15 8 -4 -17 -11 3
------------------------
-15 8 -4 -17 -11 3
------------------------
-16 -18 -3 9 -1
```

But actually, looking at the image description, it seems the grid has letters placed under certain numbers. The instruction says: "solve the riddle by matching the letters to the blank lines below."

Let’s assume that each number in the grid corresponds to a letter. The correct way to do this is to take the answers we found and match them to the numbers in the grid, then use the associated letter.

But since we don’t have the actual visual, let’s assume the grid is laid out like this (based on common worksheet formats):

There are numbers arranged in rows, and each number has a letter above or beside it.

From the problem, we see the following number-letter pairs (based on typical layout):

Let’s suppose the numbers in the grid are:

```
Row 1: 13, -16, -18, -3, 9, -1
Row 2: -15, 8, -4, -17, -11, 3
Row 3: -15, 8, -4, -17, -11, 3
Row 4: -16, -18, -3, 9, -1
```

And each number has a letter assigned to it — likely one per number.

But wait — the riddle says: "What has 13 hearts, but no other organs?" — so the answer is likely a word or phrase.

Let’s look at the answers we got:

- -8 → appears multiple times (A, F, I)
- -3 → B, R
- 3 → C, G, M
- -1 → D, N
- -11 → E
- -4 → H, J
- 10 → K
- -6 → L
- -13 → O
- -15 → P
- -12 → Q
- 8 → S

Now, the key clue is that the riddle is about something with 13 hearts, so the answer might be "a deck of cards" — because a standard deck has 13 hearts (one suit).

Let’s test that.

Riddle: "What has 13 hearts, but no other organs?"

Answer: A deck of cards

Because:
- A standard deck has 13 hearts (the heart suit).
- It has no organs — it's not alive.

So, the answer is: A deck of cards

Now, we need to verify that the math answers lead to this.

But we need to match the answers to the letters in the grid.

Wait — perhaps the grid contains letters and numbers, and we match the answer to the number, and pick the letter.

Let’s assume the grid is structured like this:

Each cell has a number and a letter. For example:

```
13 → A
-16 → B
-18 → C
-3 → D
9 → E
-1 → F
-15 → G
8 → H
-4 → I
-17 → J
-11 → K
3 → L
```

But we need to know which letter goes with which number.

Alternatively, maybe the answers go into the blank spaces in the riddle, and we fill them with letters based on the numbers.

Wait — the riddle is written as:

> What has 13 hearts, but no other organs?

And below it, there are blank lines, and the grid of numbers and letters.

So probably, the answers to the problems correspond to positions in the grid, and each position has a letter, and when you collect the letters in order, you get the answer.

But without the exact layout, we must infer.

Let’s try another approach.

Look at the answers again:

We have many repeated answers.

Let’s list the answers in the order of the problems:

1. -8
2. -3
3. 3
4. -1
5. -11
6. -8
7. 3
8. -4
9. -8
10. -4
11. 10
12. -6
13. 3
14. -1
15. -13
16. -15
17. -12
18. -3
19. 8

Now, if we look at the riddle: “What has 13 hearts, but no other organs?”

We expect the answer to be "A deck of cards" — but that’s 15 characters.

Alternatively, maybe it’s "A deck of cards", and the letters are hidden in the grid.

But perhaps the number 13 is important.

Wait — the title is "13 Hearts", and the riddle mentions 13 hearts.

So the answer is likely "a deck of cards".

Now, how do we confirm this?

Let’s suppose that the correct answers correspond to the letters in the grid.

But since we can't see the image, we rely on logic.

In such worksheets, the answers are matched to the numbers in the grid, and each number has a letter next to it.

For example, if the answer is -8, and in the grid, -8 is paired with the letter D, then you write D in the blank.

But we don’t have that mapping.

However, we can reverse-engineer.

Suppose the riddle answer is "A DECK OF CARDS".

That’s 13 letters.

But the riddle says "What has 13 hearts..." — so maybe the answer is "A deck of cards", and the blanks are for letters.

But we need to find which letter corresponds to which number.

Alternatively, perhaps the sums are used to find letters via a cipher.

But more likely: the answers are numbers, and those numbers appear in the grid, and each number has a letter associated with it.

Let’s assume the grid has:

- Numbers: 13, -16, -18, -3, 9, -1, -15, 8, -4, -17, -11, 3, etc.
- Each number has a letter.

Then, for each problem, we compute the answer, find that number in the grid, and take the letter.

Then, write the letters in order.

But without the visual, we can't do that.

However, since the riddle is well-known, and the answer is "A deck of cards", and the title is "13 Hearts", we can conclude:

✔ Final Answer:

What has 13 hearts, but no other organs?

👉 A deck of cards

Because:
- A standard playing card deck has 13 cards in the hearts suit.
- Cards are not living things, so they have no organs.

---

✔ Summary:

- Math solutions are computed correctly.
- The riddle is a classic pun.
- The answer is: A deck of cards

Even without the full grid, based on the context and common riddles, this is the intended solution.

---

Answer: A deck of cards