How many addition signs should be put between digits of 987654321 to equal 99? Where should they be placed? Time to solve 10 minutes.
9 squares puzzle: Find area of rectangle with 9 gradually smaller squares inside it and the side length of smallest square 3 units. Time 30 minutes.
Surely you can solve the 3 digit number puzzle in 20 mins if you approach the puzzle with systematic problem solving techniques.
Find area of equilateral triangle if side length of smallest of 3 squares inscribed in the triangle on top of each other is 1. It needs a bit of math.
Find the 10 digit number with each digit different and each number formed by first n digits divisible by n. Step by step solution by basic math explained.
Bank cashier mistake puzzle: Double the cheque amount less 20 paise received as Cashier interchanged paise with rupees. What were the cheque figures?
