A digital historian is trying to verify a journal entry dated in the early summer of 2099. The entry states it was written on a Monday in the first week of June 2099. Based on calendar calculations, which of the following dates could the entry have been made on?
(a) June 2
(b) June 3
(c) June 1
(d) June 5

Question

A digital historian is trying to verify a journal entry dated in the early summer of 2099. The entry states it was written on a Monday in the first week of June 2099. Based on calendar calculations, which of the following dates could the entry have been made on?
(a) June 2
(b) June 3
(c) June 1
(d) June 5

ONLiNE UPSC · Accepted Answer

From Year 1 to 2098:
Leap years = 2098 &divide; 4 - 2098 &divide; 100 + 2098 &divide; 400 = 524 - 20 + 5 = 509
Ordinary years = 2098 - 509 = 1589
Total odd days = 509 &times; 2 + 1589 &times; 1 = 1018 + 1589 = 2607
2607 &divide; 7 = 372 weeks + 3 odd days
So, 1 Jan 2099 = Monday + 3 = Thursday
From Jan to May 2099 (non-leap year):
Odd days: Jan (3) + Feb (0) + Mar (3) + Apr (2) + May (3) = 11
11 &divide; 7 = 4 odd days
So, 1 June 2099 = Thursday + 4 = Monday
Hence, option c is correct.

Calendar Calculations

Day of the Week Calculation

Website Link

Test Your Knowledge

Student Resources


M Question 1	⏱ 0
A digital historian is trying to verify a journal entry dated in the early summer of 2099. The entry states it was written on a Monday in the first week of June 2099. Based on calendar calculations, which of the following dates could the entry have been made on? (a) June 2 (b) June 3 (c) June 1 (d) June 5

Calendar Calculations

Day of the Week Calculation

Demo Session!

Demo Session Fill out the form below and hit the Join Session button to proceed.

Are you genious?

Demo Session
Fill out the form below and hit the Join Session button to proceed.