Answer:
3:2
Explanation:
Let's call the trains A and B
Train A moves from Howrah to Patna in 9 hours
Train B moves from Patna to Howrah in 16 hours
Assuming it takes 30 miles to OR from each destination,
Then train A travels 30 miles in 9 hours
Train B travels 30 miles in 16 hours
Train A's speed is 30/9= 3.33 miles per hour
Train B's speed is 30/16= 1.88 miles per hour
Ratio of their speeds(approximately,train A to train B)= 3:2