To calculate the equivalent resistance of resistors in series:
\[ R = r1 + r2 + r3 + \ldots + rx \]
Where:
Series resistance is defined as two or more components in a circuit that have resistance and are aligned in series.
Let's assume the following values:
Step 1: Sum the resistances:
\[ R = 5 + 10 + 15 = 30 \text{ Ω} \]
The equivalent resistance is 30 Ω.