Question 13
This year Ginny is 11 and has been admitted to Hogwarts. She and her brother Ron wait for the train to school at King's Cross station. She finds that three out of every ten children arriving at the station wait at Platform $9\frac34$.
1. If 50 children arrive, how many wait at Platform $9\frac34$?
2. Hogwarts holds a feast in the Great Hall to welcome new pupils. Ginny sees Headmaster Dumbledore wearing half-moon glasses and a long silver-white beard. “I wonder how old he is?” Ginny asks. Hermione replies playfully, “Age is inversely proportional to the number of years needed to complete all the charms in the magic book. I am 12, and if I need 55 years to complete them, at his age I would need only 6 years.” Ginny works out the respected headmaster's age. How old is Dumbledore?
1. If 50 children arrive, how many wait at Platform $9\frac34$?
2. Hogwarts holds a feast in the Great Hall to welcome new pupils. Ginny sees Headmaster Dumbledore wearing half-moon glasses and a long silver-white beard. “I wonder how old he is?” Ginny asks. Hermione replies playfully, “Age is inversely proportional to the number of years needed to complete all the charms in the magic book. I am 12, and if I need 55 years to complete them, at his age I would need only 6 years.” Ginny works out the respected headmaster's age. How old is Dumbledore?