Worksheet for practicing reading and writing numbers in words, digits, and expanded form.

Problem Analysis:

The task involves converting numbers between their numerical form (digits) and their written form (words). This is a fundamental exercise in understanding place value and number representation. Let's solve each part step by step.

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Part 1: Write the number in words

- Number: 278
- Solution: Two hundred seventy-eight

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Part 2: Write the number in digits

- Number in words: Four hundred twelve
- Solution: 412

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Part 3: Write each of these numbers in words

1. 624
- Breakdown:
- Hundreds place: 6 (six hundred)
- Tens place: 2 (twenty)
- Ones place: 4 (four)
- Answer: Six hundred twenty-four

2. 135
- Breakdown:
- Hundreds place: 1 (one hundred)
- Tens place: 3 (thirty)
- Ones place: 5 (five)
- Answer: One hundred thirty-five

3. 397
- Breakdown:
- Hundreds place: 3 (three hundred)
- Tens place: 9 (ninety)
- Ones place: 7 (seven)
- Answer: Three hundred ninety-seven

4. 936
- Breakdown:
- Hundreds place: 9 (nine hundred)
- Tens place: 3 (thirty)
- Ones place: 6 (six)
- Answer: Nine hundred thirty-six

5. 852
- Breakdown:
- Hundreds place: 8 (eight hundred)
- Tens place: 5 (fifty)
- Ones place: 2 (two)
- Answer: Eight hundred fifty-two

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Part 4: Write each of these numbers in digits

1. Three hundred eighty-four
- Breakdown:
- Hundreds place: 3
- Tens place: 8
- Ones place: 4
- Answer: 384

2. Four hundred sixty-one
- Breakdown:
- Hundreds place: 4
- Tens place: 6
- Ones place: 1
- Answer: 461

3. Nine hundred forty-five
- Breakdown:
- Hundreds place: 9
- Tens place: 4
- Ones place: 5
- Answer: 945

4. Seven hundred twenty-six
- Breakdown:
- Hundreds place: 7
- Tens place: 2
- Ones place: 6
- Answer: 726

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Part 5: Write each of these numbers in words

1. 307
- Breakdown:
- Hundreds place: 3 (three hundred)
- Tens place: 0 (no tens, so nothing added)
- Ones place: 7 (seven)
- Answer: Three hundred seven

2. 870
- Breakdown:
- Hundreds place: 8 (eight hundred)
- Tens place: 7 (seventy)
- Ones place: 0 (no ones, so nothing added)
- Answer: Eight hundred seventy

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Part 6: Write each of these numbers in digits

1. Two hundred eight
- Breakdown:
- Hundreds place: 2
- Tens place: 0 (no tens)
- Ones place: 8
- Answer: 208

2. Six hundred nine
- Breakdown:
- Hundreds place: 6
- Tens place: 0 (no tens)
- Ones place: 9
- Answer: 609

3. Eight hundred seventy
- Breakdown:
- Hundreds place: 8
- Tens place: 7
- Ones place: 0 (no ones)
- Answer: 870

4. Five hundred twelve
- Breakdown:
- Hundreds place: 5
- Tens place: 1
- Ones place: 2
- Answer: 512

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Final Answers:

1. Write this number in words (278):
$\boxed{\text{Two hundred seventy-eight}}$

2. Write this number in digits (Four hundred twelve):
$\boxed{412}$

3. Write each of these numbers in words:
- 624: $\boxed{\text{Six hundred twenty-four}}$
- 135: $\boxed{\text{One hundred thirty-five}}$
- 397: $\boxed{\text{Three hundred ninety-seven}}$
- 936: $\boxed{\text{Nine hundred thirty-six}}$
- 852: $\boxed{\text{Eight hundred fifty-two}}$

4. Write each of these numbers in digits:
- Three hundred eighty-four: $\boxed{384}$
- Four hundred sixty-one: $\boxed{461}$
- Nine hundred forty-five: $\boxed{945}$
- Seven hundred twenty-six: $\boxed{726}$

5. Write each of these numbers in words:
- 307: $\boxed{\text{Three hundred seven}}$
- 870: $\boxed{\text{Eight hundred seventy}}$

6. Write each of these numbers in digits:
- Two hundred eight: $\boxed{208}$
- Six hundred nine: $\boxed{609}$
- Eight hundred seventy: $\boxed{870}$
- Five hundred twelve: $\boxed{512}$

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Boxed Final Answer Summary:

$$
\boxed{
\begin{aligned}
&\text{Two hundred seventy-eight}, 412, \text{Six hundred twenty-four}, \text{One hundred thirty-five}, \text{Three hundred ninety-seven}, \\
&\text{Nine hundred thirty-six}, \text{Eight hundred fifty-two}, 384, 461, 945, 726, \text{Three hundred seven}, \text{Eight hundred seventy}, \\
&208, 609, 870, 512.
\end{aligned}
}
$$