Two charges of magnitude `-2Q and +Q` are located at points `(a,0) and (4a,0)` respectively .
What is the electric flux due to charges through a sphere of radius '3a' with its center at the origin.

Explanation

To solve the problem, we need to find the electric flux through a sphere of radius '3a' centered at the origin due to two charges: `-2Q` located at `(a, 0)` and `+Q` located at `(4a, 0)`.

### Step-by-Step Solution:

1. **Identify the Charges and Their Positions**:
- We have two charges:
- Charge 1: `-2Q` at position `(a, 0)`
- Charge 2: `+Q` at position `(4a, 0)`
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