Today's question

I suppose a four-digit number. The cube of the sum of the digits is equal to the number itself. Can you say which is the number?

Answer to Wednesday's question

The number which gives the same result when multiplied by 5/4 and when added to 5/4 is 5.

Multiplying big numbers by 11

To multiply big numbers by 11, first multiply the number by 10 and then add the original number to the product.

Example: To multiply 9876 by 11 first multiply it by 10 (9876 x 10 = 98760)
Add 9876 to 98760 (9876 + 98760 = 108636)

Mysterious 24

If you square any prime larger than 3 and subtract 1, the answer will always be divisible by 24.

Example:  19 x 19 = 361, 361 – 1 = 360

360/24 = 15

Today's question

Today’s question:

Which number when multiplied by 5/4 gives the same result as when added to 5/4?

Post your answers as comment. The answer will be published on Friday.

Magic number

Factors of 1,274,953,680

The number 1,274,953,680 has all the digits from 0 to 9. It is divisible by all the numbers from 1 to 16.

Answer to yesterday's question

The answer to yesterday’s question:

The next number in the sequence 4,6,8,9 is 10. They are the composite numbers in order.

Today's question

Today’s question:

Which is the next number of the sequence 4,6,8,9,……..?

7-11-13 trick

Ask a friend to write any three digit number on a sheet of paper.

Ask him/her to multiply the number by 7, then by 11 and finally by 13. (You can give him/her a calculator)

You will still get the answer quicker than your friend.

Trick: Just write the three digit number twice to get the answer.

Example: Let 452 be the number chosen by your friend. 452 x 7 x 11 x 13 = 452452. That is the same as 452 written two times.

Mnemonic

A mnemonic is a word, rhyme or any sentence which helps us to remember some rule, formula etc.

The following mnemonic helps us in remembering the trigonometric ratios:

Some People Have Curly Brown Hair Turned Permanently Black

Sin = Perpendicular (P)

          Hypotenuse (H)

Cos =       Base (B)    

         Hypotenuse (H)

Tan = Perpendicular (P)

              Base (B)

Answer to yesterday's question

The answer to yesterday’s question:

The smallest number exactly divisible by numbers from 1 to 10 is the numbers’ LCM which is 2520.

Today's question

Today’s question:

Which is the smallest number exactly divisible by numbers from 1 to 10?

You can attempt to answer this through your comments. The answer will be published tomorrow in our blog.

Easy multiplication

Easy method to multiply by 5:

In order to multiply a number by 5, add a 0 to right of the number or multiply by 10 and then, divide it by 2.

For example, suppose 426 is to be multiplied by 5. When a zero is added to it or it is multiplied by 10, it becomes 4260. When it is divided by 2, we get 2130. That is, 426 x 5 = 2130.

First Post

Greetings everyone! We are launching our blog here by posting the oldest number puzzle in mathematics. This was once shown in an English movie. The riddle goes like this:

As I was going to St. Ives,

I met a man with seven wives,

Every wife had seven sacks,

Every sack had seven cats,

Every cat had seven kits,

Kits, cats, sacks and wives,

How many were going to St. Ives.

This seems like a very complicated puzzle. But the answer lies in the question itself. Only one person that is, the speaker was going to St. Ives. He met the remaining people on his way. All mathematical problems are similar to this. Read the question more than once before locking an answer. It is easy to underestimate a problem and lead to a wrong conclusion. So always think twice before you act.

Our Launch

"Education is the manifestation of the perfection already in man", so said Swami Vivekananda. Herewith, we are starting a journey into the wonderful of mathematics to provide oppurtunities to all so that they may rise to their fullest potential. The world is full of oppurtunities and experiences. Every experience is an oppurtunity to learn something new. We should strive to allow the light of knowledge to create a difference in our lives. He who can rise up to a challenge and make a difference is the one with an unwavering belief in himself.  Through this blog our objective is to help each and every one of you in all possible ways, to move forward in this context. All of you are free to post any of your doubts or queries regarding mathematics and if possible they will be answered within a period of time(minimum 24 hours). We will also be including puzzles, quizzes and other interesting facts. This blog is created and run by a post graduate who has always been passionate about this subject. She will be online from 7 to 8 pm. We will start functioning from the 27th of May, 2013. Hope that the help we offer will make a difference in your search and we look forward to your support and encouragement.