In YDSE the intensities at points where path difference is `lambda` and `lambda//4` is found to be K and NK respectively. Find the value of N.

Explanation

To solve the problem, we need to analyze the situation in the Young's Double Slit Experiment (YDSE) where the path differences are given, and we need to find the relationship between the intensities at those points.

### Step-by-Step Solution:

1. **Understanding the Problem**:
We have two points with different path differences: one at \( \Delta x = \lambda \) and the other at \( \Delta x = \frac{\lambda}{4} \). The intensities at these points are given as \( K \) and \( NK \) respectively.

2. **Using the Intensity Formula**:
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