Archive for the ‘Conundrum’ Category
Conundrum 2 : Middle Three Digits
A five-digit perfect square in the form of 5abc6 has a thousands digit a, hundreds digit b, and tens digit c. If a is less than or equal to b and b is less than or equal to c, what is the sum of a + b + c?
Conundrum I : Help Varun!
Varun and Rahul sit together, Rahul asks varun find the sum of the sum of the digits of all natural numbers upto 10. Varun quickly answers 46. Rahul again asks what if we find upto 50, varun takes some time and answers 330. Rahul stands up and says, Can you find it for 2008, and do it before I count upto 20?
Your task is to help Varun, How will you do that?
