1."My five children were all born two years apart," Don declared. Steve nodded. "But how old are they now?" Don thought a moment. "Put it this way," he replied. "If you divide the square of the age of the oldest by a certain whole number you get the total of their ages." Well?

Ages 10, 12, 14, 16 and 18 years

Ages 13, 15, 17, 19 and 21 years

Ages 12, 14, 16, 18 and 20 years