Question: how to calculate the probability of rolling doubles?
Answer: To calculate your chance of rolling doubles, add up all the possible ways to roll doubles (1,1; 2,2; 3,3; 4,4; 5,5; 6,6). There are 6 ways we can roll doubles out of a possible 36 rolls (6 x 6), for a probability of 6/36, or 1/6, on any roll of two fair dice.