Double Digit Multiplication Worksheet with Nine Problems for Practice

The task involves solving double-digit multiplication problems. Below, I will solve each problem step by step and provide the final answers.

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Problem 1: \( 19 \times 12 \)

1. Break down the multiplication:
- Multiply \( 19 \) by \( 2 \): \( 19 \times 2 = 38 \)
- Multiply \( 19 \) by \( 10 \): \( 19 \times 10 = 190 \)

2. Add the results:
- \( 38 + 190 = 228 \)

Answer: \( 228 \)

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Problem 2: \( 45 \times 16 \)

1. Break down the multiplication:
- Multiply \( 45 \) by \( 6 \): \( 45 \times 6 = 270 \)
- Multiply \( 45 \) by \( 10 \): \( 45 \times 10 = 450 \)

2. Add the results:
- \( 270 + 450 = 720 \)

Answer: \( 720 \)

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Problem 3: \( 25 \times 25 \)

1. Use the formula for squaring a number:
- \( (a + b)^2 = a^2 + 2ab + b^2 \)
- Here, \( a = 20 \) and \( b = 5 \):
- \( 25^2 = (20 + 5)^2 = 20^2 + 2(20)(5) + 5^2 \)
- \( 20^2 = 400 \)
- \( 2(20)(5) = 200 \)
- \( 5^2 = 25 \)
- Add them together: \( 400 + 200 + 25 = 625 \)

Answer: \( 625 \)

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Problem 4: \( 20 \times 10 \)

1. Multiply directly:
- \( 20 \times 10 = 200 \)

Answer: \( 200 \)

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Problem 5: \( 13 \times 23 \)

1. Break down the multiplication:
- Multiply \( 13 \) by \( 3 \): \( 13 \times 3 = 39 \)
- Multiply \( 13 \) by \( 20 \): \( 13 \times 20 = 260 \)

2. Add the results:
- \( 39 + 260 = 299 \)

Answer: \( 299 \)

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Problem 6: \( 32 \times 17 \)

1. Break down the multiplication:
- Multiply \( 32 \) by \( 7 \): \( 32 \times 7 = 224 \)
- Multiply \( 32 \) by \( 10 \): \( 32 \times 10 = 320 \)

2. Add the results:
- \( 224 + 320 = 544 \)

Answer: \( 544 \)

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Problem 7: \( 21 \times 40 \)

1. Multiply directly:
- \( 21 \times 40 = 840 \)

Answer: \( 840 \)

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Problem 8: \( 24 \times 11 \)

1. Use the distributive property:
- \( 24 \times 11 = 24 \times (10 + 1) = (24 \times 10) + (24 \times 1) \)
- \( 24 \times 10 = 240 \)
- \( 24 \times 1 = 24 \)
- Add them together: \( 240 + 24 = 264 \)

Answer: \( 264 \)

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Problem 9: \( 26 \times 18 \)

1. Break down the multiplication:
- Multiply \( 26 \) by \( 8 \): \( 26 \times 8 = 208 \)
- Multiply \( 26 \) by \( 10 \): \( 26 \times 10 = 260 \)

2. Add the results:
- \( 208 + 260 = 468 \)

Answer: \( 468 \)

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Final Answers:

\[
\boxed{
\begin{array}{ccc}
228 & 720 & 625 \\
200 & 299 & 544 \\
840 & 264 & 468
\end{array}
}
\]