Answer :
The train travels at 5.5km per hour.
We know that in x hours it will advance by x*5.5 km.
Hence we need to solve x*5.5=82.5, hence x=82.5/5.5=15
It will take 5 hours
We know that in x hours it will advance by x*5.5 km.
Hence we need to solve x*5.5=82.5, hence x=82.5/5.5=15
It will take 5 hours