Answer:
10 hours
Explanation:
Just do it as pages over time in minutes.
p/t = 45/90 and putting 45/90 in the lowest terms is 1/2 and so he reads a page every two minutes.
In that case, it’s going to take him 600 minutes to read the whole book. To get that in hours, just put the minutes taken over 60
600/60 = 10.