Let the age of Gopal be X Let his grandmother’s age be Y Let his grandfather’s age be Z Given, Age of Gopal is one third of his grandfather’s age X = Z /3 The age of his grandmother is 6years less than his grandfather Y = Z – 6 Given, X + Y + Z = 113 Z/3 + Z – 6 + Z = 113 7Z – 18 = 339 7Z = 357 Z = 51 Age of Gopal’s grandfather is 51 His grandmother’s age is 6 years less than his grandfather. So, His grandmother’s age is 45 Hence, “45” is the correct answer.