Explanation : (C) Shopkeeper uses a weight of 800 g instead 1 kg, so that gain
= 1000 - 800 x100
      800
= 200 /800 xl00 = 25%
His profit will be 25%.
Explanation : (C) 1729 is "Hardy" Ramanujan number, because it is the smallest number expressible as the sum of two cubes in two different ways, i.e. 1729 =13 +Â 123 = 93 + 103Â