Answer:
C. 8 hours.
Explanation:
Let x be the number of hours spent while traveling by train and y represent number of hours spent while traveling by plane.
We have been given that Tom spent same number of hours by plane and by train, so we can represent this information in an equation as:

The train covers 50 miles in 1 hour, so distance covered by train in x hours would be 50x.
The plane covers 275 miles in 1 hour, so distance covered by plane in y hours would be 50x.
We have been given that Tom took a trip of 1300. We can represent this information in an equation as:

Substituting equation (1) in equation (2) we will get,




Since
, therefore,
.
To find the total time spent we need to add x and y.

Therefore, the trip took 8 hours and option C is the correct choice.