Long division practice: divide 2-digit numbers by 3-digit numbers with step-by-step solutions.

To solve the given long division problems, we will perform each division step by step. Let's go through each problem:

---

Problem a) \( 42 \div 939 \)

1. Set up the division:
\[
42 \longdiv{939}
\]

2. Divide the first two digits of the dividend (93) by the divisor (42):
- \( 93 \div 42 \approx 2 \)
- Multiply: \( 42 \times 2 = 84 \)
- Subtract: \( 93 - 84 = 9 \)

3. Bring down the next digit (9):
- New number: 99

4. Divide 99 by 42:
- \( 99 \div 42 \approx 2 \)
- Multiply: \( 42 \times 2 = 84 \)
- Subtract: \( 99 - 84 = 15 \)

5. The quotient is 22 with a remainder of 15.

\[
\boxed{22 \text{ R } 15}
\]

---

Problem b) \( 56 \div 868 \)

1. Set up the division:
\[
56 \longdiv{868}
\]

2. Divide the first two digits of the dividend (86) by the divisor (56):
- \( 86 \div 56 \approx 1 \)
- Multiply: \( 56 \times 1 = 56 \)
- Subtract: \( 86 - 56 = 30 \)

3. Bring down the next digit (8):
- New number: 308

4. Divide 308 by 56:
- \( 308 \div 56 \approx 5 \)
- Multiply: \( 56 \times 5 = 280 \)
- Subtract: \( 308 - 280 = 28 \)

5. The quotient is 15 with a remainder of 28.

\[
\boxed{15 \text{ R } 28}
\]

---

Problem c) \( 26 \div 937 \)

1. Set up the division:
\[
26 \longdiv{937}
\]

2. Divide the first two digits of the dividend (93) by the divisor (26):
- \( 93 \div 26 \approx 3 \)
- Multiply: \( 26 \times 3 = 78 \)
- Subtract: \( 93 - 78 = 15 \)

3. Bring down the next digit (7):
- New number: 157

4. Divide 157 by 26:
- \( 157 \div 26 \approx 6 \)
- Multiply: \( 26 \times 6 = 156 \)
- Subtract: \( 157 - 156 = 1 \)

5. The quotient is 36 with a remainder of 1.

\[
\boxed{36 \text{ R } 1}
\]

---

Problem d) \( 21 \div 862 \)

1. Set up the division:
\[
21 \longdiv{862}
\]

2. Divide the first two digits of the dividend (86) by the divisor (21):
- \( 86 \div 21 \approx 4 \)
- Multiply: \( 21 \times 4 = 84 \)
- Subtract: \( 86 - 84 = 2 \)

3. Bring down the next digit (2):
- New number: 22

4. Divide 22 by 21:
- \( 22 \div 21 \approx 1 \)
- Multiply: \( 21 \times 1 = 21 \)
- Subtract: \( 22 - 21 = 1 \)

5. The quotient is 41 with a remainder of 1.

\[
\boxed{41 \text{ R } 1}
\]

---

Problem e) \( 31 \div 965 \)

1. Set up the division:
\[
31 \longdiv{965}
\]

2. Divide the first two digits of the dividend (96) by the divisor (31):
- \( 96 \div 31 \approx 3 \)
- Multiply: \( 31 \times 3 = 93 \)
- Subtract: \( 96 - 93 = 3 \)

3. Bring down the next digit (5):
- New number: 35

4. Divide 35 by 31:
- \( 35 \div 31 \approx 1 \)
- Multiply: \( 31 \times 1 = 31 \)
- Subtract: \( 35 - 31 = 4 \)

5. The quotient is 31 with a remainder of 4.

\[
\boxed{31 \text{ R } 4}
\]

---

Problem f) \( 34 \div 994 \)

1. Set up the division:
\[
34 \longdiv{994}
\]

2. Divide the first two digits of the dividend (99) by the divisor (34):
- \( 99 \div 34 \approx 2 \)
- Multiply: \( 34 \times 2 = 68 \)
- Subtract: \( 99 - 68 = 31 \)

3. Bring down the next digit (4):
- New number: 314

4. Divide 314 by 34:
- \( 314 \div 34 \approx 9 \)
- Multiply: \( 34 \times 9 = 306 \)
- Subtract: \( 314 - 306 = 8 \)

5. The quotient is 29 with a remainder of 8.

\[
\boxed{29 \text{ R } 8}
\]

---

Final Answers:

\[
\boxed{
\begin{aligned}
a) & \quad 22 \text{ R } 15 \\
b) & \quad 15 \text{ R } 28 \\
c) & \quad 36 \text{ R } 1 \\
d) & \quad 41 \text{ R } 1 \\
e) & \quad 31 \text{ R } 4 \\
f) & \quad 29 \text{ R } 8
\end{aligned}
}
\]