A record has been playing 1/3 hour the record still has 1/12 hour to play. What is is the total length of time the record will play, in...

The record will play for a total of 5/12 of an hour, which can also be expressed as 25 minutes.  Here's how to go about figuring that out.

When you have to add fractions with different denominators, you have to convert them so they have the same denominator.  In this case, you can convert 1/3 to have 12 as its denominator.  You do this by multiplying it by 4.  When you do that, you get 4/12.

Since the record has played 4/12 hours and has 1/12 left to go, it will play for 5/12 total.

To convert this into minutes, you must know that one hour = 60 minutes.  So then you must figure out how many minutes make up 1/12 of an hour.  Divide 60/12, that gives you 5.

So 1/12 hour = 5 minutes.  Therefore 5/12 hours = 25 minutes.