Thanks ina advance
1.How many distinct subsets of the set S=1,8,9,39,52,91 have odd sums? (As an example, 1,8,52 is one such subset, because 1+8+52 equals 61, which is odd.)
2.How many distinct subsets of the set S=1,8,9,39,52,91 have three-digit sums? (As an example, 39,91 is one such subset, because 39+91 equals 130, which has three digits.)
3.Consider the set S=1,2,3,4,5,6,7,8,9,12,13,14,15,16,17,18,19,23,24,. . . . ,123456789\}, which consists of all positive integers whose digits strictly increase from left to right. This set is finite. What is the median of the set?
