Follow the clues to find the mystery number.
What do the digits in the number fifteen add up to? How many other
numbers have digits with the same total but no zeros?
A church hymn book contains 700 hymns. The numbers of the hymns are
displayed by combining special small single-digit boards. What is
the minimum number of small boards that is needed?
Can you substitute numbers for the letters in these sums?
Did you know? Mathematical problems in which you replace digits with letters that make words or even phrases are called CRYPTARITHMS.