He read 8 pages every day for 12 days for a total of 8*12 = <<8*12=96>>96 pages

96 pages is the same as two-thirds of the total number of pages which means: number of pages*(2/3) = 96

Therefore the total number of pages is 96*(3/2) = <<96*(3/2)=144>>144 pages

# Answer

144
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
Bill started reading a book on the first day of April. He read 8 pages every day and by the 12th of April, he had covered two-thirds of the book. How many pages does the book have?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
144
Bill started reading a book on the first day of April. He read 8 pages every day and by the 12th of April, he had covered two-thirds of the book. How many pages does the book have?
train