This worksheet helps students practice counting by 10s, 100s, and 1000s using abacus visuals and number sequences.

Problem Analysis and Solution

The worksheet involves counting in multiples of 10s, 100s, and 1000s, as well as identifying patterns and filling in missing numbers. Let's solve each part step by step.

---

#### Part 1: Counting in 10s, 100s, and 1000s

We are given the number 4825 and asked to perform the following operations:

1. 10 more than 4825
- Adding 10 to 4825:
\[
4825 + 10 = 4835
\]
- Answer: 4835 (already filled in the worksheet).

2. 100 less than 4825
- Subtracting 100 from 4825:
\[
4825 - 100 = 4725
\]
- Answer: 4725.

3. 1000 more than 4825
- Adding 1000 to 4825:
\[
4825 + 1000 = 5825
\]
- Answer: 5825.

---

#### Part 2: Identifying Patterns

We are given sequences of numbers and asked to identify the next three numbers in each pattern.

1. Sequence 1: 2347, 3347, 4347, ...
- Observing the pattern: Each number increases by 1000.
\[
2347 + 1000 = 3347, \quad 3347 + 1000 = 4347
\]
- Continuing the pattern:
\[
4347 + 1000 = 5347, \quad 5347 + 1000 = 6347, \quad 6347 + 1000 = 7347
\]
- Next three numbers: 5347, 6347, 7347 (already filled in the worksheet).

2. Sequence 2: 8801, 8811, 8821, ...
- Observing the pattern: Each number increases by 10.
\[
8801 + 10 = 8811, \quad 8811 + 10 = 8821
\]
- Continuing the pattern:
\[
8821 + 10 = 8831, \quad 8831 + 10 = 8841, \quad 8841 + 10 = 8851
\]
- Next three numbers: 8831, 8841, 8851.

3. Sequence 3: 3451, 3351, 3251, ...
- Observing the pattern: Each number decreases by 100.
\[
3451 - 100 = 3351, \quad 3351 - 100 = 3251
\]
- Continuing the pattern:
\[
3251 - 100 = 3151, \quad 3151 - 100 = 3051, \quad 3051 - 100 = 2951
\]
- Next three numbers: 3151, 3051, 2951.

---

#### Part 3: Writing Missing Numbers

We are given sequences with missing numbers and asked to fill them in.

1. Sequence 1: 3861, 3761, ____, ____, ____, 3361
- Observing the pattern: Each number decreases by 100.
\[
3861 - 100 = 3761, \quad 3761 - 100 = 3661, \quad 3661 - 100 = 3561, \quad 3561 - 100 = 3461
\]
- Missing numbers: 3661, 3561, 3461 (already filled in the worksheet).

2. Sequence 2: 581, 591, ____, ____, ____, 631
- Observing the pattern: Each number increases by 10.
\[
581 + 10 = 591, \quad 591 + 10 = 601, \quad 601 + 10 = 611, \quad 611 + 10 = 621
\]
- Missing numbers: 601, 611, 621.

3. Sequence 3: ____, 2111, ____, ____, 1711
- Observing the pattern: Each number decreases by 100.
\[
2111 - 100 = 2011, \quad 2111 - 100 = 2011, \quad 2011 - 100 = 1911, \quad 1911 - 100 = 1811
\]
- Missing numbers: 2211, 2011, 1911.

---

Final Answers

1. Part 1:
- b. 100 less than 4825: 4725
- c. 1000 more than 4825: 5825

2. Part 2:
- Sequence 2: 8831, 8841, 8851
- Sequence 3: 3151, 3051, 2951

3. Part 3:
- Sequence 2: 601, 611, 621
- Sequence 3: 2211, 2011, 1911

Boxed Final Answer

\[
\boxed{4725, 5825, 8831, 8841, 8851, 3151, 3051, 2951, 601, 611, 621, 2211, 2011, 1911}
\]