How to calculate day using your fingers?
31 oct 2016
The date must be minus by 7 or 14 or 21 or 28 if it is smaller than 7.
Therefore, 31 - 28 = 3
There is no need to minus if the date is smaller than 7.
For 2016, we need to add 5 to the number 3 = 8. If this year is a leap year (29 feb exists), then we need to add 1 after feb, so it will be 6+3 = 9 and 5+3=8 for Jan & Feb.
For every additional year in the future (without leap year), we just increase the number by 1. For e.g., 2017 is to add 6, 2018 is to add 7. Once the number reaches 7, it will be reset to zero again and this cycle starts all over again.
Looking at the diagram, October is the first section of the index finger. As we need to add 5 to 3 = 8, we just count the first section (october) as 1 and move downward 8 times which will end at the first section of index finger (Monday).
Thus, 31 october 2016 falls on Monday.
How to calculate date using your fingers?
What date is last Sunday of October 2016
October is 1st section of index finger.
Since 2016 is to add 5, we will just count the first section (october) as 1 and move downward 5 times which will end at the 2nd section of the middle finger (Friday). Thus, the next day will always be the 1st date or day of the month (1st oct). Since we are trying to find the last Sunday, the first Sunday falls on the 2nd date which is 2nd October 2016.
Just do a simple calculation to get the date for last sunday.
1st sunday, 2 October 2016 (add 7 to get the next sunday)
2nd sunday, 9 October 2016 (add 7 to get the next sunday)
3rd sunday, 16 October 2016 (add 7 to get the next sunday)
4th sunday, 23 October 2016 (add 7 to get the next sunday), Continue to add 7 if less than 31
5th sunday, 30 October 2016
Therefore, the answer is 30 October 2016.
Please take note of leap year as you will need to apply the same logic above.