Two fair, six-sided dice are rolled. What is the probability that the sum of the two numbers showing is less than 11?

The probability that they show 12 is 1/36

The probability thatt hey show 11 is 2/36

So.....the probability that they show  11 or more = 3/36  = 1/12

So....the probability that they show less than 11 = [1 - 1/12]  = 11/12