To find the unit rate, divide the total number of pages by the total amount of time:
Unit rate = Total number of pages / Total amount of time
In this case, the total number of pages is 144 and the total amount of time is 3 minutes:
Unit rate = 144 pages / 3 minutes
Simplifying this expression:
Unit rate = 48 pages per minute
Therefore, the unit rate of 144 pages in 3 minutes is 48 pages per minute.