A person reaches his destination 40 minutes late if his speed is 3 km/hr and reaches 30 minutes before time if his speed is 4 km/hr. What is the distance of his destination from the starting point? (in km)

Given:
A person reaches his destination 40 minutes late if his speed is 3 km/hr and reaches 30 minutes before time if his speed is 4 km/hr.
Let the distance be $$x$$ km.
According to the question:
- At 3 km/h → 40 minutes late
- At 4 km/h → 30 minutes early
Thus, the total time difference is:

​$$40 + 30 = 70 \text{ minutes} = \frac{7}{6} \text{ hours}$$

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