just like our body needs exercise to stay fit, our brain is also like a muscles which needs exercise and doing mental calculations is the best exercise for the brain.
We know that people go to the gym for exercising, to tone their muscles and to remain healthy and active. In the same way, it has been researched that if exercised and used very often, our brain weight may increased up to 5%. Our brain behave like plastic once expanded does to return to its original size, in the same way, brain weight once increased cannot be reduced.
Just as a machine work smoothly once when used regularly with proper oiling, in the same way, we can ensure the smooth functioning of our brain when proper oiling in the form of mental work in the right direction, is provided to it.
Exercising brain not only helps to calculate fast, but also in our daily activities. The efficiency of the whole process of thinking and taking action is accelerated substantially in our day- to- day decisions.
So, to have a smart and fast bring, we must exercise it as often as possible as performing mental calculations serves as a mental gym for our brain, keeping it fit and active.
While doing calculation with calculator, our involvement in the process of calculation nil. This is highly dangerous in the long run, as we lose our ability to calculate in day- to- day life and our thinking ability is also affected. Mental math’s, on the contrary, helps to sharpen our calculating ability.
500 Years Calendar
Now, let’s learn amazing techniques of mastering 500 years. Calendar on your fingertips, i.e. using this techniques, you can instantly tell the day on which any particular date of a given year falls.
You can amaze your friends and relatives by telling the day on which they were born on hearing their birth dates in less than 5 seconds. The technique is very useful in competitive exams, where questions related to dates and ages re to be answered.
Calculating the day of any particular date
if we observe any date, there are 4 main things – date, month, century and year. Each of these has different codes. The sum of all these codes helps in determining the day of the week on which any given falls.
Let’s understand it by the following example:
Example 1:
Find the day of 23rd may, 1992.
For date: Divide the date by 7. Write the remainder as the code of the date.
23 : 7 gives 2 as remainder
So, code for date (23) is 2.
For month: each month has a unique code. Below is the table showing codes for all 12 months.
This final sum 7 will tell the day has its own code as shown in the table below:
Table 4:
Day Code
Sunday 1
Monday 2
Tuesday 3
Wednesday 4
Thursday 5
Friday 6
Saturday 0 and 7
Since, 7 corresponds to Saturday, so the day on 23rd may, 1992 was Saturday.
Some more examples:
Finds days on which the following dates fall:
Example 2:
28th March, 1980
Date = 28 : 7 gives Remainder = 0
Month = March = 4 (refers table 1)
Year = 1980 = 0 + 2= 2 (refers table 2 and 3)
Adding all we get 0 + 4 + 2 = 6.
6 is the code corresponding to Friday.
So, 28th March, 1980 was Friday.
Example 3:
5th April, 2010
Date = 5 : 7 gives Remainder = 5
Month = April = 0
Year = 2010 = 6 + 5 = 11
Total = 5 + 0 + 11 = 16
Again 16 + 7 gives remainder = 2
2 stand for Monday.
Note: when the final total is more than 7, divide it again by 7 and the remainder thus obtained corresponds to the code of the day.
Example 4: 18th Nov, 1984
Date = 18 : 7 gives remainder = 4
Month = Nov = 4
Year = 1984 = 0 + 0 = 0
Total = 4 + 4 + 0 = 8
Again 8 : 7 gives remainder = 1
1 stands for Sunday.
Example 5: 15th August, 1947
1 + 3 + 0 + 2 = 6
6 stands for Friday
