Question

Friends have a party. Joyce invited 17 friends to a dinner party at her house last Friday

evening. She gave each guest a card with a number from 2 through 18, reserving the
number 1 for herself. When she had everyone paired off at the dinner table, she noticed
that the sum of each couples' number was a perfect square. What number did Joyce's
partner have?

Answer 1

15

Explanation:

Joyce reserved number 1 for herself

Of all the possible combinations,

1 and 15 is a perfect match for a perfect square

So,Joyce dinner partner was number 15.