Maths Puzzles

1. The number 121 is a perfect square. In a decimal system. In which other number system, is 121 a perfect square?           Bonus : Let us look at another puzzle based on different bases. 2. What is the missing number in the following sequence: 10, 11, 12,13, 14, 15, 16, 17, 20, 22, 24, 31, 100, - - , 10,000. (Hint: The missing number is in ternary notation)  Find the solutions to these puzzles here .  

 Here was the puzzle 91.   John inherited from his uncle 25% more money than his sister Helen. He wants to give her part of his money to have the same amount as her. What percentage of his money should he give to Helen? Let us say that John's sister inherited x rupees.   John inherited 25% more than her. Let us say his inheritance is y. y = 0.25x + x = 1.25x x = y/1.25 The extra amount received by John is 0.25x Extra amount = 0.25x = 0.25 X  y/1.25  = y/5 = 0.2 y To divide this equally among both, he has to give half of this amount to his sister.  John should give 0.2 y/2 = 0.1 y = 10% of y to his sister.

John inherited from his uncle 25% more money than his sister Helen. He wants to give her part of his money to have the same amount as her. What percentage of his money should he give to Helen?   Find the solution here. 

  There are as many four-legged chairs and as many four-legged tables as workers in the office of Yamraj, and as many three-legged stools as four-legged almirahs. If the number of stools be one more than number of workers and the total number of legs be 585,then what is the number of workers in the office?

 As a part of festival sale, one shop offers 50% discount on a particular watch. The next shop offers 30% discount on the same watch, then additional 20% discount after the first discount is applied. Which shop offers the cheaper price?

 Puzzle 88 asked you to draw 8 equilateral triangles using only 6 equal length line segments.  Here is the much familiar diagram for you.  Two equilateral triangles, forming six more.  Who knew the only rangoli I could draw will be a solution to a mathematical puzzle? Do you know any other solutions to this puzzle?