Joe is learning to play the trumpet. on Monday he practiced from 6:30 until 7:05. on Tuesday he practiced from 3:55 until 4:15. how many minutes did he practice in all over the two days.?

Let's start with day 1:

We know that Joe practiced from 6:30 to 7:05

An hour is 60 minutes

Joe practiced for the 30 minutes left in that hour and 5 minutes into the next

30+5=35

So, he was playing for 35 minutes on the first day

Now, we can do the same thing for the second day:

He started at 3:55 and ended at 4:15

An hour is 60 minutes

Joe practiced for the 5 minutes left in the hour and the first 15 minutes of the next hour

5+15=20

Now we want to add the number of minutes he practiced for both days

35+20=55 minutes