Who does not like to head! And if the story is a funny intellectual exercise, then there is nothing to say. One such book is a number game . This is the Bengali translation of Russian mathematician Yakov Perelman's famous book Figures for Fun: Stories, Puzzles and Conundrums . Published by Pragati Publications of the former Soviet Union (now Russia) translated by Bimalendu Sengupta. The editor was naturalist Dwijen Sharma. The book is full of fun math tricks, brain teasers and brain teasers.

Panchmishali puzzle

I hope that the book is very useful to the readers. It is also hoped that the book not only gives pleasure, but also helps to increase intelligence and creative power, to put knowledge to better use. After reading the book, you will definitely want to play the brain a little. A variety of puzzles are provided in this section to fulfill your wishes.

Chicken and duck eggs

There are chicken and duck eggs in the baskets. Some have chicken eggs and some have duck eggs. How many eggs are in a basket is written on the basket. There are 5, 6, 12, 14, 23 and 29 eggs. The shopkeeper said, 'If I sell this basket, the duck's eggs will be twice as many as the chicken's eggs.

sky travel

An airplane takes 1 hour 20 minutes to reach from A to B and only 80 minutes to return. How to explain it?

gift money

The two sons were each given some money by their father. One gave his son 150 rubles, the other gave 100 rubles. The boys counted their money and saw that their money had increased by only 150 rubles. How did it happen?

Two draft knobs

Place two different colored balls anywhere in the 64 cells of the table. Tell me how they can be kept?

solution

1. The egg dealer thought of a basket of 29 eggs. The baskets marked 23, 12 and 5 contained chicken eggs, and the baskets marked 14 and 6 contained duck eggs.

Let's look at the answer. After sale there will be 23 + 12 + 5 = 40 chicken eggs and 14 + 6 = 20 duck eggs.

Then according to the riddle, chicken eggs will be twice as much as duck eggs.

2. There is nothing to explain here. The plane takes off, and it comes back at the same time. Because 80 minutes and 1 hour 20 minutes are the same thing. The puzzle is actually provided for the other-minded reader. He might think that there is some difference between 80 minutes and 1 hour 20 minutes.

3. The trick is, one of them is the father, the other is the father's son. There are only three people in the puzzle, not 4. Grandpa, father and son. Grandfather gave 150 rubles to his son, he again gave 100 rubles to his grandson (ie his son). Then his own money remained only 50 rubles.

4. A knob can be placed in any of the 64 rooms. That is, there are 64 ways to put it. When this is done there are only 63 rooms left to hold the second one. That means, any of the 64 states of the first node can be added to any of the 63 states of the second node. Then there are 64 × 63 = 4,032 different positions for placing two knots on the draft table.