A box contains tiles, numbered 1, 2, 3,..., 49, 50. Only tiles which are marked with a number congruent to 2 mod 8 are blue. One tile is chosen randomly from the box. What is the probability that the tile is blue?
{1, 2, 3, ........50} mod 8 ==2
You have the following numbers: 2, 10, 18, 26, 34, 42, 50 ==7 integers congruent to 2 mod 8
Therefore, the probability is: 7 / 50