from 6:30-7:50 is what

Question

i need an answer to my basic math problem that is all i want. 

Answer 1

I hope that it is from two different hour, although you have to state if both hours are AM or PM or one AM and the other PM because it changes radically the answer.

from 6:30-7:50, there is a difference of 1 hour and 20 minutes, or 80 minutes; from  6:30-7:30 there is 1 hour and from 7:30 to 7:50 there are  another 20 minutes.

I hope this was the question. 

Answer 2

assuming it is the same day and military time, it is 80 minutes or 1 hour and 20 minutes