A bag contains 88 red​ marbles, 22 blue​ marbles, and 11 green marble. What is the probability that a randomly selected marble is not​ blue?

use the concept that Bob showed you here:

http://www.jiskha.com/display.cgi?id=1470754142

To find the probability that a randomly selected marble is not blue, we need to consider the total number of marbles and the number of marbles that are not blue.

The total number of marbles in the bag is the sum of the number of red, blue, and green marbles:
Total number of marbles = 88 + 22 + 11 = 121

The number of marbles that are not blue is the sum of the number of red and green marbles:
Number of non-blue marbles = 88 + 11 = 99

So, the probability that a randomly selected marble is not blue is given by:
Probability = Number of non-blue marbles / Total number of marbles
Probability = 99 / 121 ≈ 0.818

Therefore, the probability that a randomly selected marble is not blue is approximately 0.818, or 81.8%.