Select the correct answerA train after covering 2/7 part of distance reduced its speed by 21.66% and reached certain destination 65 min late. Find the present time taken by train to cover the complete distance?Options5 hours 47 minutes7 hours 21 minutes7 hours6 hours 34 minutes

This problem can be solved by using the concept of relative speed and time. Here are the steps:

1. Let's assume the total distance to be covered is 7 units (since the train covers 2/7 of the distance initially).

2. Let's also assume the original speed of the train is x units/hour.

3. The time taken to cover the initial 2 units of distance at speed x is 2/x hours.

4. After reducing its speed by 21.66%, the new speed of the train becomes 0.7834x units/hour (since 100% - 21.66% = 78.34%).

5. The time taken to cover the remaining 5 units of distance at the reduced speed is 5/0.7834x hours.

6. The total time taken by the train to cover the complete distance is therefore 2/x + 5/0.7834x hours.

7. We know that the train is 65 minutes (or 65/60 = 1.0833 hours) late. Therefore, the original time it should have taken to cover the distance is 2/x + 5/0.7834x - 1.0833 hours.

8. Now, we need to solve this equation for x, and then substitute x back into 2/x + 5/0.7834x to find the present time taken by the train to cover the complete distance.

Unfortunately, without further information or numerical options for x, we cannot solve this problem completely. The options provided do not seem to correspond to values of x that would satisfy the equation.