Complete Reasoning Course: Calendars

Complete Reasoning Course Summary

• "Complete Reasoning" teaches reasoning in 35 hours using 750 questions.
• The course is divided into three parts, of approximately 12 hours each.
• The initial chapter focuses on Calendars and is available in both English and Hindi.
• Designed for beginners without prior reasoning knowledge.
• Students should complete all three parts without distractions.
• The course encompasses 750 chapter-specific questions with detailed explanations.
• Reviews and course sharing are encouraged among viewers.
• The course aims to be a primary resource for reasoning preparation.
• It spans 17 chapters suitable for both English and Hindi speakers.
• Students can expect to solve 90-95% of questions on Indian exams after completion.
• The speaker is a three-time topper and CBI officer.
• The course builds a strong foundation for handling most reasoning questions.
• Practice with miscellaneous questions is key to achieving 100% accuracy.
• A compilation of the 750 questions will be available on Bihar's Telegram channel.
• An additional course with the top 1000 most difficult questions is available.
• The top 1000 question course includes chapter-wise compilation of difficult questions.
• The top 1000 question course provides classes and PDFs, similar to paid content.
• The top 1000 question course is offered at an offer price of 499 (original 999).
• It is recommended to complete/revise the free course before enrolling in the paid one.
• Post-course, the speaker advises concentrating on tests for exam preparation.
• Enrollment links for the paid course are in the description and comment box.

Complete Maths Course Mention

• There's a "Complete Maths" course of 45 hours.
• Find it by searching "Complete Maths by Abhishek Ojha Sir" or "Complete Maths by Yoddha".
• The mathematics course features over 600 questions.
• It covers number systems, LCM/HCF, percentage, and profit/loss.
• Viewers are encouraged to take both reasoning and maths courses.
• Dedicate 2 hours daily to both reasoning and math.
• Complete notes and leave comments for both classes.
• The maths course has garnered over 900,000 views.

Message to Students

• Classes should be shared, especially with those who cannot afford fees.
• Some students are underprivileged and depend on these classes.
• The emphasis is on quality content without unnecessary talk.

Start of Calendar Topic

• The Calendar topic is taught with type, concept and best approaches.
• Complete viewing will allow answering of questions automatically.
• The presenter guarantees direct solutions to exam questions after completion.

Gregorian Calendar

• The Gregorian calendar is the most commonly used.
• It was created/updated by Gregory.
• Gregory updated the Roman calendar to fix errors.
• The Gregorian calendar is a solar calendar, based on the sun.
• Solar calendars are based on the sun, lunar on the moon.
• India's national calendar, the Saksh Samvat, is lunar-based.
• Saksh Samvat includes months like Chaitra.
• Exams primarily use Gregorian calendars.

Earth's Orbit

• Earth orbits the Sun in 365 days, 5 hours, 48 minutes, and 47.5 seconds.
• The Sun remains fixed, while the Earth orbits from west to east.
• Each year accumulates about 6 extra hours.
• These hours sum up to approximately 24 hours after 4 years.

Types of Years

• Years are ordinary or leap years.
• Ordinary years have 365 days; leap years have 366.
• February has 28 days in ordinary years, 29 in leap years.
• Leap years have an extra day.
• Divide the last two digits by 4 to check whether it's a leap year.
• If divisible by 4, it's a leap year (e.g., 2024).

Rule For Century Years

• Century years must be divisible by 400 to qualify as leap years.
• If a century year is divisible by 400 then it is a leap year.
• The year 2100 will not be a leap year.
• The rule compensates for the approximate nature of the 6 hours.

Defining Odd Days

• Odd days represent the remaining days after forming weeks from a date.
• This definition of odd differs from the mathematical one.
• 15 days equals two weeks (14 days) with one day remaining.
• The one extra day is defined as an odd day.
• 50 days creates 7 full weeks, 1 odd day.

Ordinary Years and Odd Days

• To find odd days in an ordinary year, divide 365 days by 7.
• 365 days divided by 7 equals 52 weeks and 1 remaining day.
• Ordinary years have one odd day.
• Leap years have two odd days.

Odd Days In Years

• This forms the basis for a useful formula for quickly solving calendar problems.
• Odd days in an ordinary year is 1.
• Odd days in an leap year is 2.

Deriving Odd Days In 100 Years

• This is how to find odd days in first hundred years.
• All years have at least one odd day, so add 100 to total count of odd days from start.
• Count all the additional odd days from the leap years.

Divide 100 by 4 = 25

• The 100th year can't be a leap year in this situation.

Because for it to be a century year leap year, it must be divisible by 400

• Only 24 leap years exist.
• Total odd days -> 100 + 24.
• This gives a remainder of 5.

This is what is meant by extra days -> the number 5

Likewise 200 years gives 3 extra days; 300 gives 1 extra day, and 400 gives -> 0

• The numbers 5, 3, 1, 0 can be discussed,.
• These are remainder values and the pattern cycles from 5.

This is how to solve 100 years calendar based problems.

More Odd Day Examples From Book

If today is Friday, what will be the days after 72 days

• 72 / 7 = Remainder of 2.
• We add 2 days to Friday to find Sunday.

Remember -> We add to move ahead, subtract to move backwards

Example

• If we have 185 days ahead -> Divide by 7, remainder is 3, so we move 3 days ahead of current day.
• If it says 365 days ahead, divide by 7, remainder of 1, move 1 day ahead.
• Move backwards if subtracting.

How many days in a year occur the maximum 53 times?

There is only ever 1 odd day

• So only one day can be repeated 53 times.
• All other days occur the normal amount during the 52 week cycle.

How many leap years exist over 400 years?

• Leap years = 4 -> Roughly every 4 years there is a leap year.
• Total Leap Years = 400 / 4 = 100
• Remember the century leap year rule -> must divide by 400.

Each 100 contains a century that is also a non leap year 100, 200, 300

• But 400 contains 400 that is indeed a leap year.
• Subtract 3 from 100 means there are 97 leap years.

How many times will February 29th occur from the consecutive 400 years

• 97, same as the number of leap years.
• Each month has a 29th (except February on non leap years).

Months except Non Leap February all contain 29

• 400 years * 11 = 4400.
• So 11 months every year will have their 29th (except leap year).
• In a 400 year period, this repeats 4400 times.
• There re 97 leap years in the cycle.
• 4400 + 97

What about the 1st day / last day of the country!

Gregorian knew - 1st month, 1st day etc -> that will be Monday

• 100 years has 5 extra days, so add from this Monday..
• 200 years has 3 extra days, so add from the original first Monday.
• 3rd century has 1 extra day, so add from the original Monday.
• 400 has no days, so same day.

Monday, Tuesday, Thursday, and Saturday can be calendar days. Others cannot

• First day could not be Wednesday, Fridays.
• Same exercise shows how final day cannot be.

Here's how to the find the first day / last day. First day is those days. Last day move 1 day previous from first day -> Example given

Another Category -> What was the actual day of this date

There are 5 steps

• Date Step -> Odd Number of Dates
• Month Code -> Magic number, know it well! Different values in leap vs non-leap. Remember this! Values given
• Century Code -> Based on rules. Need value and formula. Given
• Year Odd Days
• Leap Years In Date!

Add Them Up and The Remainder Tells You The Date

• Monday
• Tuesday
• Wednesday
• Thursday
• Friday
• Saturday
• Sunday

These question and date patterns can be solved quickly.

Solving calendar days only takes seconds with sufficient knowledge

• Ensure that the material has been digested.
• The important thing is practice.

Another Type Of Question -> What Days Can The Century Actually Start One

• Add the odd days in a century with the day Mon
• First day of century could be be Mon, Tues, Thurs, Sat

So what the day last day of the past century?

• Subtract one day from one of the possible first days.

This is one way that can be done

Another Type -> Determine The Number of days after

• All related, but important we can quickly all solve.

Here We Go To Calendar Completion-> Does That Year Repeat

• This is based on the number of week days repeat

Check How a standard Year works

• 365 = 52 weeks + 1 day
• Basically all the weeks are repeated 52 days, the extra day just adds on top.
• Same Day End
• So the only way to get same day same time is repeat a entire set of days.

It's important to check for leap years, and what type of remainder. The remainder pattern matters as each number maps to different year

Another Category

How many times 29 Feb

• Depends on number of leap years.

Another category is a date and what was the!

Remember that you will not like this class, can get same and then minus to get back

In Ordinary years first and always occur 52, last odd is what decides.

• Just calculate if it's in between the months.

Remember the repitition pattern for each date

Here is a summary of what has been covered.

• This information enables solutions for the end date, first date, and leap year problems.