Answer:
The total number of marbles in the bag is 6 (blue) + 5 (yellow) + 3 (white) + 1 (red) = 15 marbles.
The probability of an event happening is typically calculated as the number of successful outcomes divided by the total number of outcomes.
In this case, the successful outcomes are the scenarios where a marble is drawn, and it is not blue. There are 5 yellow marbles, 3 white marbles, and 1 red marble. That's a total of 5 + 3 + 1 = 9 marbles that are not blue.
So, the probability of drawing a marble that is not blue is 9 (non-blue marbles) divided by 15 (total marbles), which simplifies to 3/5 or 0.6 when expressed as a decimal.
So the probability of not selecting a blue marble is 0.6 or 60%.