SAT Prep Question (look in description)

Question

A telephone company charges x cents for the first minute of a call and charges for any additional time at the rate of y cents per minute. If a certain call costs $7.75 and lasts more than one minute which of the following represents the length of the call in minutes?

 

The answer to this question is 775-x+y/y 

I just need an explanation as to why.

Answer 1

775 - x represents the charges after the first minute.

(775 - x) / y represents the minutes after the first minute

now add the first minute

(775 - x) / y  + 1

(775 - x + y) / y