In this article, we will be aiming at various calendar problem’s tricks and concepts which is going to save your time while solving these types of questions.
Calendar Problem Concepts
First, let’s brush up basic concepts to which we already familiar with:
- 1 week = 7 days
- 1 year = 365 days or 366 days
A normal year has 365 days, consisting of 52 weeks and one extra day. On the other hand, a leap year has 366 days, consisting of 52 weeks and two extra days. A leap year always repeat after 4 years.
- Normal year = 365 days = 52 weeks and 2 extra days
- Leap year = 366 days = 52 weeks and 1 extra day (one extra days Occurs in the February Month = 29 days)
To check Whether a year is a leap year or not?
A year that consists of 366 days is known as a leap year. It is easy to know which year is a leap year. Let’s have a look:-
- If the given year is divisible by 4 and not divisible by 100 then it is a leap year. If the given year is divisible by 100 then we need to follow the second step to check whether it is a leap year or not.
- For example, 2016 is a leap year, since it is divisible by 4 but not 100. however, for the year 2000, we find that it divisible by 4 but also by 100 too, in such cases we can’t say it is a leap year or not, for this we have to follow 2nd step.
- If the given year is divisible by 100, then it should also be divisible by 400 in order to be qualified as a leap year.
- Since 2000 is also divisible by 400, it is a leap year.
Now lets come to the Calendar tricks you should know:
Week codes
| Century | Code |
|---|---|
| 1600 | 6 |
| 1700 | 4 |
| 1800 | 2 |
| 1900 | 0 |
| 2000 | 6 |
| 2100 | 4 |
| 2200 | 2 |
| 2300 | 0 |
Month codes
- For Normal years
| Month | Code |
|---|---|
| January | 0 |
| February | 3 |
| March | 3 |
| March | 6 |
| May | 1 |
| June | 4 |
| July | 6 |
| August | 2 |
| September | 5 |
| October | 0 |
| November | 3 |
| December | 5 |
- For Leap years
| Month | Code |
|---|---|
| January | 6 |
| February | 2 |
| March | 3 |
| March | 6 |
| May | 1 |
| June | 4 |
| July | 6 |
| August | 2 |
| September | 5 |
| October | 0 |
| November | 3 |
| December | 5 |
Century codes
| Century | Code |
|---|---|
| 1600 | 6 |
| 1700 | 4 |
| 1800 | 2 |
| 1900 | 0 |
| 2000 | 6 |
| 2100 | 4 |
| 2200 | 2 |
| 2300 | 0 |
Types Questions Asked from Calendar Problem
Directly Asking what day will be on a particular date
Case 1: For Normal or ordinary Year
Case 2: For Leap Year
Directly Asking which day will be after the given number of days from the mentioned day
Step to solve it:
Step 1. Divide the given number of days by 7 and find the remainder
Step 2. Add the given remainder to corresponding week code, and the resultant code will be our answer
Q. If today is Thursday then after 15 days, the day will be?
Step 1. 15/7 = Quotient 2, Remainder 1
Step 2. Thursday = 4, 4+1 = 5 , refers to Friday
Can ask which would be the very first mentioned day in a given month of a year
Need to perform a basic addition operation
Q. When will be the first Friday fall in the month of July 2019?
On 1st July 2019, the day will be Monday by using the method mentioned in the above example. On 5th July will be first Friday
In this, date along with day will be given and using that day as a base, you need to figure out what will be the day for the asked date
Just find an extra or odd day in between the years and add extra days only if February of that month covers. In a leap year, there are 2 extra days and in Normal year there is only one odd day
Q If 26th May 2018 falls Saturday then What day will be on 26th May 2019
Between this, Only a single February falls which is in the year 2019. So we add only odd days of 2019, skipping 2018
Day on 26th May 2018 = Saturday = 6
Odd days in the year 2019 is = 1
6+1= 7
So, 26th May 2019 falls on Sunday.
Below are some practise question for Calendar Problem:
Question. What would be the day on 25th January 1950?
Answer Wednesday
Question. If the day on 4th October 2018 was Thursday, then what will be the day on 2nd February 2019?
Answer Saturday
Question. What will be the day on 20th May 2030?
Answer Monday
Question. When will be the first Sunday fall in the month of July 2024?
Answer 6th July 2024
