Answer:
21.25 days
Explanation:
We first need to find the rate that he read the book for the first 5 days:
180 (pages)/5 (days)= 36
So he reads 36 pages a day. Now we need to find how many days it will take him to read the whole book, while reading 36 pages a day.
765 (total pages)/36 (pages he reads in a day) = 21.25
Have a wonderful day, my friend.