Math Crossword 1 - Free Printable

To solve the math crossword puzzle, we need to compute each of the arithmetic operations given in the clues and fill in the corresponding squares in the grid. Let's go through the calculations step by step.

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Across:

1. 21 - 8
\( 21 - 8 = 13 \)

2. 159 - 13
\( 159 - 13 = 146 \)

3. 465 + 770
\( 465 + 770 = 1235 \)

4. 1290 - 300
\( 1290 - 300 = 990 \)

5. 297 + 1289
\( 297 + 1289 = 1586 \)

6. 235 + 152
\( 235 + 152 = 387 \)

7. 25 + 21
\( 25 + 21 = 46 \)

8. 1792 - 1344
\( 1792 - 1344 = 448 \)

9. 27 + 2
\( 27 + 2 = 29 \)

10. 54 + 35
\( 54 + 35 = 89 \)

11. 12300 - 5879
\( 12300 - 5879 = 6421 \)

12. 540 + 1355
\( 540 + 1355 = 1895 \)

13. 12 + 35
\( 12 + 35 = 47 \)

14. 560 + 180
\( 560 + 180 = 740 \)

15. 21 + 24
\( 21 + 24 = 45 \)

16. 811 + 1139
\( 811 + 1139 = 1950 \)

17. 61 - 8
\( 61 - 8 = 53 \)

18. 17 + 44
\( 17 + 44 = 61 \)

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Down:

1. 1498 + 930
\( 1498 + 930 = 2428 \)

2. 64 - 15
\( 64 - 15 = 49 \)

3. 183 - 86
\( 183 - 86 = 97 \)

4. 338 - 42
\( 338 - 42 = 296 \)

5. 283 + 1492
\( 283 + 1492 = 1775 \)

6. 9785 - 7344
\( 9785 - 7344 = 2441 \)

7. 15 - 4
\( 15 - 4 = 11 \)

8. 9124 - 1589
\( 9124 - 1589 = 7535 \)

9. 27 - 2
\( 27 - 2 = 25 \)

10. 3292 - 778
\( 3292 - 778 = 2514 \)

11. 836 - 15%
First, calculate 15% of 836:
\( 15\% \times 836 = 0.15 \times 836 = 125.4 \)
Then subtract:
\( 836 - 125.4 = 710.6 \)

12. 1 + 15%
First, calculate 15% of 1:
\( 15\% \times 1 = 0.15 \)
Then add:
\( 1 + 0.15 = 1.15 \)

13. 12345 - 7685
\( 12345 - 7685 = 4660 \)

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Filling the Grid:

Using the computed values, we can fill in the crossword grid. Here is the completed grid:

```
1 2 3 4 5
1 1 3 1 4 6
2 9 7 5 9
3 1 2 3 5 8
4 9 9 0 6
5 1 5 8 6 3
6 8 7 5 5
7 2 4 2 8 4
8 4 9 7 7
9 1 4 6 2 1
10 4 6 2 5
11 6 4 2 1 6
12 1 7 7 5
13 7 5 3 5 4
14 7 4 0 4
15 4 5 1 1 5
16 1 9 5 0
17 7 1 0 . 6
18 1 . 1 5
19 6 1 - 8 .
20 1 7 + 4 4
```

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Final Answer:

The completed crossword grid is as shown above. The final boxed answer is:

\[
\boxed{61}
\] (from Down clue 18)