there is 40 chapters
my opinion is 40th day
If the one pack a day smoker has a habit for 40 years, that would come to 20 cigarettes X 365 days per year X 40 years. If that smoker had a two pack a day habit, then the answer would need to be doubled.
The Day I Swapped My Dad for Two Goldfish has 40 pages.
Every day at 13:30 and 4:40-5:55
He had a 40 year Army career.
40 minutes. 24 miles is two thirds of 36. Two thirds of an hour is 40 minutes.
Ascension day falls always 40 days after the Easter and the month of it is May.
If a day took 40 hours, then a day would take 40 hours.
AR 40-66
DA PAM 385-40 -- Army Accident Investigations and Reporting
Zachary Taylor had 40 years of service in the US Army.