Question

Cody tells Gordon that he is thinking of a number between 10 and 30 the clues he gave are (a) that the sum of the digits is 9 and (b) that the number is odd. What correct answer did Gordon give?

Answer 1

27. You can do this by thinking of all the pairs that add up to 9( 1 and 8, 2 and 7, 3 and 6, 4 and 5) and arrange them to get numbers.