1. **Stating the problem:** We have a sequence of cycles counted at cycle stands: 0, 6, 12, 18, and a missing value at the fifth position. The cycle stands are numbered 0, 1, 2, 3, 4. We need to find the missing number of cycles at cycle stand 4. 2. **Understanding the relationship:** The problem states that there are 6 cycles per cycle stand. This means the number of cycles increases by 6 for each increment in cycle stand. 3. **Formula used:** The number of cycles $C$ at cycle stand $n$ can be expressed as: $$C = 6 \times n$$ where $n$ is the cycle stand number. 4. **Applying the formula:** For cycle stand 4: $$C = 6 \times 4 = 24$$ 5. **Conclusion:** The missing value of cycles at cycle stand 4 is 24.