Answer: The required number of pages is 67.5.
Step-by-step explanation: Given that we can read 45 pages of our new book in 2 hours.
We are to find the number of pages that we can read in 3 hours.
We will be using the UNITARY method to solve the given problem.
Number of pages that can be read in 2 hours = 45.
So, number of pages that can be read in 1 hour is

Therefore, the number of pages that can be read in 3 hours is given by

Thus, the required number of pages is 67.5.