Students can use this worksheet to practice writing ordinal numbers in both numerical and word formats.

Problem Explanation:

The task involves working with ordinal numbers. Ordinal numbers are used to indicate the position or order of things (e.g., first, second, third). The worksheet has two parts:

1. Part A: Convert ordinal number words into their numerical form.
2. Part B: Convert ordinal numbers in numerical form into their word form.

Let's solve each part step by step.

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Part A: Write the ordinal numbers.

#### Instructions:
Write the numerical form for the given ordinal number words.

#### Solutions:
1. thirteenth
- The word "thirteenth" corresponds to the 13th position.
- Numerical form: 13th

2. seventh
- The word "seventh" corresponds to the 7th position.
- Numerical form: 7th

3. nineteenth
- The word "nineteenth" corresponds to the 19th position.
- Numerical form: 19th

4. first
- The word "first" corresponds to the 1st position.
- Numerical form: 1st

5. twenty-fifth
- The word "twenty-fifth" corresponds to the 25th position.
- Numerical form: 25th

#### Final Answers for Part A:
1. 13th
2. 7th
3. 19th
4. 1st
5. 25th

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Part B: Write the ordinal numbers in words.

#### Instructions:
Write the word form for the given ordinal numbers in numerical form.

#### Solutions:
1. 16th
- The numerical form "16th" corresponds to the word "sixteenth."
- Word form: sixteenth

2. 4th
- The numerical form "4th" corresponds to the word "fourth."
- Word form: fourth

3. 22nd
- The numerical form "22nd" corresponds to the word "twenty-second."
- Word form: twenty-second

4. 10th
- The numerical form "10th" corresponds to the word "tenth."
- Word form: tenth

5. 28th
- The numerical form "28th" corresponds to the word "twenty-eighth."
- Word form: twenty-eighth

#### Final Answers for Part B:
1. sixteenth
2. fourth
3. twenty-second
4. tenth
5. twenty-eighth

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Final Answer:

\[
\boxed{
\text{Part A: 1) 13th, 2) 7th, 3) 19th, 4) 1st, 5) 25th}
}
\]
\[
\boxed{
\text{Part B: 1) sixteenth, 2) fourth, 3) twenty-second, 4) tenth, 5) twenty-eighth}
}
\]