Sum modulo 12 and divisor of 4
Find the modulo 7 of the sum of the modulo 12 and its divisor of 4
How to play:
In order to improve speed and confidence in your date-to-weekday conversions, it’s instumental that you practice to quickly combine calculations in the doomsday algorithm.
In this game, you will practice finding the sum of two numbers and apply the modulo 7 on it.
The first number is the modulo 12 of the last two digits of the year. If you haven’t already, you should first be confident in the Modulo 12 game.
The second number is the divisor of 4 of the number above. This is the largest whole number that can evenly divide the number by 4. See the Divisor of 4 game to practice this operation.
Finally you must take the sum of these numbers and find the modulo 7 of it. This will be your answer to the round.
Here are some examples:
1904
04 % 12 = 4
⌊4/4⌋ = 1
(4 + 1) % 7 = 5
1913
13 % 12 = 1
⌊1/4⌋ = 0
(1 + 0) % 7 = 1
1935
35 % 12 = 11
⌊11/4⌋ = 2
(11 + 2) % 7 = 6
1966
66 % 12 = 6
⌊6/4⌋ = 1
(6 + 1) % 7 = 0
1991
91 % 12 = 7
⌊7/4⌋ = 1
(7 + 1) % 7 = 1
2027
27 % 12 = 3
⌊3/4⌋ = 0
(3 + 0) % 7 = 3