What resistance must be connected to a 15 ` Omega ` resistance to provide an effective resistance of 6`Omega ` ?

Explanation

To find the resistance that must be connected to a 15 Ω resistor to provide an effective resistance of 6 Ω, we will follow these steps:

### Step 1: Understand the Configuration
Since the effective resistance (6 Ω) is less than one of the resistances (15 Ω), we can conclude that the two resistances are connected in parallel.

### Step 2: Write Down the Formula for Parallel Resistance
The formula for the effective resistance (R_P) of two resistors R_1 and R_2 in parallel is given by:
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