Let x be the age of Jill, who is the youngest. The the Jac's age is 3x, while the Jon age is 3*(3x) = 9x. Jon is 16 yaers older than Jill 9x - x = 16. It implies 8x = 16 x = 16/8 = 2. So, Jill is 2 years old. Hence, Jac is 3x = 3*2 = 6 years old. ANSWER